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Ratooning is the agricultural practice of harvesting a monocot crop by cutting most of the above-ground portion but leaving the roots and the growing shoot apices intact so as to allow the plants to recover and produce a fresh crop in the next season. This practice is widely used in the cultivation of crops such as rice, sugarcane, banana, and pineapple. Ratoon crops cannot be perennially renewed, and may be harvested only for a few seasons, as a decline in yield tends to occur due to increased crowding, damage by pests and diseases, and decreasing soil fertility.

History

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The earliest record for ratooning, in a crop plant, can be traced back to the Vedic period in India. The Atharvaveda mentions that farmers cultivating barley (yava) used to cut barley plants many a time (20/125/2, Richa or Shloka No. 5755).[1][unreliable source?]

Chinese records of sugarcane ratooning exist from 1757, in Fujian Province.[2]

Etymology

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The word ratoon probably owes its origin either from the Latin words retonsus, meaning 'to cut down' or retono, which means 'to thunder back' or 'resound'.[3] In Spanish, the close words retoño and retoñar mean 'sprout' and 'to sprout'.[3]

Terminology of ratooned crops varies, based on how far the crop extends from the original planting. The first harvest is called the plant crop,[3] main crop[4] or principal crop.[4] Subsequent harvests are called first ratoon, second ratoon, etc.[3][4]

In sugarcane

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Ratooning is an ancient method of propagation in sugarcane in which subterranean buds on the stubble (the part of cane left underground after harvesting) give rise to a new crop stand, which is usually referred to as the 'ratoon' or the 'stubble crop' as opposed to 'plant crop', which is raised from seeds or seedlings. Ratooning reduces the cost of cultivation by dispensing with additional seed material and some cultural practices such as land preparation and preparatory irrigation (palewa). It also results in early ripening of canes by at least a month or so, thus it adds to the effective crushing period. Sugarcane has a tremendous ratooning potential, and the oldest cultivated ratoon, being ratooned since 1757, in East China, in Fujian Province, stands to its testimony. The number of ratoons in sugarcane production cycles varies throughout the world, i.e., from one plant crop in Indonesia and some parts of China, one plant crop and a ratoon crop in India, Fiji and some parts of China, to six or more successive ratoons in Mauritius, Cuba, Venezuela, clayey soils of Zimbabwe, some parts of Puerto Rico, etc. The latter is also referred to as multiple ratooning. A decline in cane yield in successive ratoon crops, the so-called "ratoon decline", on the order of 20%, had been reported from many sugarcane-growing areas in India; the decline is more (up to 40% ) in subtropical India. Causes for this decline are: poor ratoon management, inherited differences in potential (ratoon) productivity, increasing incidence of diseases (like smut, grassy shoot disease, and red rot) which result in stands with gaps (studies conducted in India have shown that a gap over 10% significantly affects productivity of a ratoon crop), relatively less efficient enzyme systems (particularly nitrate reductase) activity, in vivo and prevalence of low temperatures during harvest, especially for early-ripening varieties and ratoon crop(s) in subtropical India which affects sprouting of stubble buds, etc. Insect pests also assume importance in a ratoon crop as stubble acts as a 'carry-over' of the inocula of pests both for coming up ratoon and for the neighbouring sugarcane crop(s), improperly looked-after crop gets infested by a number of insect pests, emerging sprouts of a ratoon crop favour rapid development and multiplication of some of the insect pests, and insect associated with stubble affect sprouting causing gaps which ultimately affect productivity of the ratoon crop, per se.

In Indian context, in subtropical India, ratoon initiated during spring (March) resulted in higher number of millable canes, cane yield and sucrose % juice in comparison to ratoon crops initiated either in winter (January) or summer (May). In peninsular India, however, as the sugarcane crop does not suffer extremes of weather conditions during summer and winters, differences in time of planting and harvest do not significantly influence the yield of succeeding ratoon crop.[5][6]

Such a decline could be effectively prevented by proper ratoon management. Need for the latter stems from the famous Kalai (Aligarh, India) experiments conducted during 1939-1949.[7] A good example of ratoon management and multiple ratooning is from Hoshalli village (in district Shimoga, Karnataka, India) where good yields of sugarcane ratoon crop (125-134 t/ha) were harvested year after year since 1968 without much loss in cane yield and quality. The crux for such a success was trash mulching, application of lime and irrigation after harvest of the crop every year.[8] Ratooning has now become so much important in sugarcane production system that ratooning ability has become one of the important selection criteria for release of sugarcane varieties for commercial cultivation.

Assessment of ratooning ability

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Yield of ratoon crop is a function of yield potential and its ratooning ability. The latter, by and large, envisages the extent of multiple ratooning and their relative yield performance as compared to corresponding plant crop. In India sugarcane varieties cultivated prior to introduction of Co varieties were not ratooned because of their susceptibility to insect-pests and diseases.[9] Incorporation of S. spontaneum genome into modern sugarcane varieties has contributed to ratooning ability.[10][11] The latter has been assessed by dry matter production of above ground parts at periodic harvests (at four-month intervals),[11] the ratio of performance (of NMC and/or cane weight) of ratoon crop vs. plant crop.[12] Characters like higher plant cane yield, stalk population and sprouting of stubble buds are useful in selecting good ratooners.[13] Ratoon x environment interaction were high in varieties with poor ratooning ability[14] and inherited differences in potential productivity appear to be responsible for ratoon decline.[15] In Jamaica to calculate decline in ratoon productivity a Ratoon Performance Index (RPI) is used.[16]

In India, the second major sugarcane growing country, among the sugarcane varieties released and notified from 2000 to 2015 for commercial cultivation Co 85004, Co 2001–13, Co 2001-15 Co 0218, Co 0403, Co 86249, Co 0237, CoPk 05191 are good ratooners and CoPant 90223, CoS 95255, CoS 94270, CoSe 92423 have been rated to be the excellent ratooners.[17]

Growth and development of ratoon crop vis-à-vis plant crop

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Buds on the lower half of the stubble give rise to most of the shoots in a ratoon.[18] Initially, emerging shoots, for their development, depend on the nutrients stored in the stubble and for water supply on the roots attached to the stubble. Using the techniques of Panwar et al.,[19] roots remain active up to 106 days after harvest although they are relatively less efficient in nutrient uptake, possibly due to suberization and ageing. The new root system (shoot roots from the developing shoots) develop in 6–8 weeks after harvest subject to soil and weather conditions. Ghosh et al. observed that, per unit root weight, shoots developed relatively more in the settlings raised from stubble buds as compared to those from top cane buds.[20]

Experiment at Kalai (Aligarh, in sub-tropical India) indicated that the maximum number of tillers were attained by July and maximum number of canes (NMC) increased gradually in the subsequent ratoons and it was also associated with increased tiller mortality. In response to manuring, NMC gradually increased in succeeding ratoons. The average cane weight (ACW) is relatively lesser in ratoon crops and it gradually decreased in subsequent ratoons. Manuring also increased ACW by 62-75%.[7] Interaction to space is relatively more pronounced in a ratoon crop as compared to its corresponding plant crop[21] and perhaps due to this ratoon crops can tolerate a gap of 10% without any appreciable reduction in cane yield.[22] Since optimal temperatures for tillering is 33.3–34.4 °C,[23] winter-harvest of crop adversely affects tillering in an upcoming ratoon. If ratoon is initiated in April, tillering is profuse but mortality is high with poor growth of shoots. With successive ratooning, arrowing (flowering) increases.[24]

Why a ratoon crop ripens earlier than its corresponding plant crop

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A ratoon crop ripens earlier, in general, by at least one to one and a half months or so due to: early development of shoots,[25] maintenance of relatively lesser N content in index tissues,[26] rapid run-out of N during grand growth phase[27] and relatively higher inorganic non-sugars in its juice.[28]

Poor ratoon crops due to low temperature harvest

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In subtropical India, in crops which are harvested from November to mid-January, due to prevalence of low temperatures result in poor sprouting of stubble buds and the succeeding ratoon crop is invariably poor. Buds located on the stubble remain dormant and sprout only when favourable temperatures are available in February. This could be managed by either foliar application of growth regulators before harvest of plant crop or giving some treatments to the stubble of the freshly harvested crop. In the former, among various treatments used application of Ethrel + urea was more effective.[29] Among the later, treatments like (a) stubble protection by spreading polyethylene cover,[30] loosening soil around stubble,[30] and trash mulching and irrigation at 10–15 days interval,[19] (b) maintaining optimal clump population by gap filling using dug-out stubble, pre-germinated settlings, sprouts from clumps in the growing ratoon crop,[5][6] (c) improving cultural conditions by intercropping with suitable varieties of guar, cow pea, moong and potato[5][6] and (d) application of growth regulating substances to the stubble of freshly harvested cane like Cycocel[31][32] help to sustain ratoon productivity under such conditions.

Need for ratoon management

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Need for ratoon management stems from its being an integral component of sugarcane production system, contributing to over half the cane acreage (it may increase when multiple ratooning is practiced); and as compared to corresponding plant crop, a ratoon crop has superficial roots, early shoot growth has to depend upon relatively less efficient root system (roots on the stubble), relatively less efficient enzyme system (especially the NRA), is infested/ infected more by insect-pests and diseases, ripens early and suffers ratoon decline.[citation needed]

The ICAR-Indian Institute of Sugarcane Research, Lucknow has identified certain technologies for ratoon management like dismantling of ridges, stubble shaving and off-barring at initiation of ratoon; gap filling when there is more than 45 cm distance (gap) between clumps; paired-row system of planting (120p x30) to reduce gaps and optimize plant population; trash mulching in alternate rows so as to conserve soil moisture, manage weeds and maintain soil organic carbon, etc. They have also designed and developed a tractor operated two-row Ratoon Management Device (RMD) to perform field operations for ratoon cultivation such as stubble shaving, deep tilling, off-barring, application of manure, fertilizers, bio-agents, etc., and finally earthing-up in a single pass to manage ratoon crop (0.35-0.4 ha/h) so as to improve its productivity. It also saves 60% on the cost of cultivation.[33]

Studies on ratooning ability, overcoming ratoon decline, and early ripening of ratoons will be desirable in times to come.[fact or opinion?]

Specific applications

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The main benefits of ratooning are that the crop matures earlier (by one and half month or so) in the season and also decrease the cost of field preparation, preparatory irrigation as well as seed cane used for planting. By early maturing may increase the effective crushing duration of sugar mill adding to sugar production. At some places ratooning sugarcane (for short duration ratoon crops) has also been utilized to provide quality fodder for cattle.

Multiple ratooning of sugarcane, with proper management including plant protection, may be utilized for maintaining purity of new improved varieties as well as genetically modified plants, for a longer period of time.

Being endowed with high rates of CO2 fixation, enormous capacity for storage of soluble compounds, metabolic transformation systems and containment of its genes, ensured by its vegetative propagation make sugarcane a desirable plant for its use as a bio-industry for synthesis of value–added products (molecular farming). Using biotechnological tools, the latter has been accomplished for the synthesis of p-hydroxy benzoic acid,[34][35] sorbitol,[35] and isomaltulose.[36] In this endeavour, vast ratooning potential could be more helpful in containing desirable genes in such genetically modified plants for sufficiently longer rather more faithfully.[fact or opinion?]

Other crops

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Besides sugarcane, ratooning is also practiced commercially in many other crops. Examples include banana, cotton, mint, pearl millet, pigeon peas, pineapple, ramie, rice, and sorghum.[3][4] Ratooning is frequently used on plants that will be processed for essential oils, fiber, and medicines.[3]

Ratooning is most often used with crops which are known to give a steady yield for three years under most conditions.[citation needed] For example, the woody desert shrub guayule, an alternative source of natural rubber, is first harvested at two years, then ratooned annually in spring with a final crop that includes both tops and roots.[37]

Rice is grown as a monocarpic annual plant. However, in tropical areas it can serve as a perennial,[38] producing a ratoon crop,[38] and may survive for up to 30 years.[citation needed]

References

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Further reading

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Revisions and contributorsEdit on WikipediaRead on Wikipedia

Ratooning

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from Grokipedia
Ratooning is an agricultural practice involving the cultivation of successive crops from the regrowth of stubble and roots left in the after the initial , without the need for replanting, thereby enabling multiple yields from a single planting. The term "ratoon" derives from the Spanish "retoño," meaning a young shoot or sprout. This method primarily applies to crops and monocots such as , , and , where subterranean buds on the remaining stubble produce new shoots. Originating from early observations of natural regrowth in tropical regions, ratooning has been employed for centuries, with historical records dating back to ancient practices in sugarcane propagation and documented use in cultivation as early as the Western Jin Dynasty in . In modern , it accounts for 50–75% of global cultivation area and is increasingly adopted for in to enhance amid climate challenges. Common applications include up to 4–5 ratoon cycles in for and double-cropping in China's Fujian Province for , where improved varieties have boosted yields from 6.7 to 12.3 tonnes per hectare. The practice offers significant economic and environmental advantages, including 25–30% reductions in production costs through savings on labor, planting materials, and , as well as lower energy use—ratoon sugarcane requires approximately 89 million calories per ton compared to 205 million for initial plantings. It also improves by minimizing disturbance and enabling harvests before seasonal floods, while enhancing crop quality, such as higher content in ratoon (16.54% versus 14.84% in plant cane). However, challenges persist, including gradual yield declines over cycles due to nutrient depletion and disease accumulation, necessitating genotype selection for strong ratooning ability influenced by factors like parentage and environmental management. Recent advancements, such as , optimized nitrogen application (150 kg/ha), and 2024 guidelines in promoting mechanized ratoon rice with demonstration yields of 8.99 tonnes per hectare in the ratoon season, have revitalized its potential, promoting sustainable intensification in low-input systems across and beyond.

Fundamentals

Definition and Mechanism

Ratooning is an agricultural cultivation method in which the above-ground parts of a are harvested, leaving the roots and basal shoots—collectively referred to as stubble—intact to enable regrowth and subsequent harvests from the same . This practice is primarily suited to or monocotyledonous crops that possess robust vegetative capabilities, allowing them to regenerate without the need for complete replanting. The biological mechanism of ratooning centers on the activation of dormant buds located at the base of the stubble, on underground rhizomes, or along root systems, which sprout to form new tillers or shoots. Physiologically, this regrowth is supported by the remobilization of stored reserves, such as carbohydrates and , from the stubble and , providing essential energy and nutrients for early development before the new shoots can photosynthesize effectively. Hormonal signals, including auxins and cytokinins, further regulate the process by breaking bud and stimulating tillering, ensuring coordinated shoot elongation and lateral branching. Key principles of ratooning emphasize its dependence on crops with strong vegetative reproduction traits, which enable efficient sprouting from existing structures rather than seed . In contrast to annual replanting, where new systems must develop from scratch, ratooning leverages pre-established for rapid initial growth and better , reducing the time to maturity. This approach is particularly effective in monocot crops like grasses, which naturally profusely, while dicot crops typically show limited regrowth potential due to weaker basal . Historically, ratooning has been a primary example in production.

Etymology

The term "ratoon" derives from the Spanish "retoño," meaning a young sprout or shoot, which itself stems from the "retoñar," to sprout, combining the prefix "re-" (intensive or repetitive action, from Latin) with "otoñar," to grow in autumn, ultimately from Latin "autumnus." This Spanish origin reflects the influence of Iberian agricultural practices on colonial economies, with the word entering English in the mid-18th century via trade and systems in the . The earliest documented use of "ratoon" as a appears in , in the agricultural observations of Robert Robertson, a Scottish minister in , where it described the regrowth of after harvest. Linguistically, "ratoon" initially functioned as a noun denoting the secondary crop or shoots emerging from stubble, as seen in 18th-century texts on estates. By the late 1700s, it extended to the form "to ratoon," signifying the act of allowing or managing such regrowth, and subsequently to "ratooning" as the nominalized practice in agricultural . This shift paralleled the expansion of intensive in tropical regions, where the term became standardized in English by the early . In distinction from related concepts, "ratooning" specifically emphasizes multi-season regrowth from perennial roots in crops like sugarcane, differing from "stubble cropping," which typically applies to annual cereals regrowing briefly from residual stems without long-term root reliance. Equivalent terms in other languages include French "repousse" or "culture de repousse," referring to the aftergrowth or ratoon harvest, often used in contexts of forage or tropical perennials. Early applications of the term centered on sugarcane contexts in colonial agriculture.

Historical Development

Origins

Ratooning practices trace their roots to ancient Asian , where the regrowth of crops after harvesting was observed and utilized for grains and -like plants. In , ratooning emerged as an established technique by the West Jin Dynasty (AD 265–316), allowing farmers to obtain a second crop from the stubble of the main harvest, a method documented in historical agricultural records as a means to extend yields in subtropical regions. Similarly, in , cultivation dates back at least 3,000 years, with early textual references in works like the (circa 300 BCE) describing the crop's management, implying the use of regrowth practices akin to modern ratooning in tropical settings. The term "ratoon" itself derives from the Spanish retoño, meaning "sprout," highlighting the linguistic influence of Iberian agricultural traditions on the practice. During the colonial era, European powers disseminated ratooning to the alongside , transforming it into a cornerstone of economies. colonizers introduced to in 1532, establishing the first mills in where ratooning enabled multiple harvests from initial plantings, boosting export-oriented production in the Northeast. Spanish explorers followed suit in the , planting on as early as 1493 and adopting ratoon cycles to sustain labor-intensive estates across islands like and by the mid-16th century. In the , British planters in systematically documented and refined ratoon cycles on sugar estates, integrating them into annual operations to minimize replanting costs amid expanding slave-based . Contemporary accounts, such as those in estate management records, detail how enslaved laborers handled ratooning tasks during the "dead season" from August to November, including stubble preparation and weeding to support up to three successive crops per planting. This documentation, later compiled in guides like Thomas Roughley's 1823 Jamaica Planter's Guide, underscored the economic rationale of ratooning in colonial contexts, where it extended productivity on cleared lands.

Global Adoption

The practice of ratooning in cultivation expanded significantly during the 19th century, particularly in British India and , as colonial agricultural systems adapted to meet surging industrial demand for sugar in Europe and beyond. In British India, ratooning was integrated into emerging commercial production, especially along the , where industrial sugar factories proliferated to capitalize on the crop's regrowth potential for multiple harvests per planting cycle. This expansion was driven by falling global sugar prices and rising consumption, prompting producers to rely on multi-ratoon cycles—often two to three successive harvests—to reduce replanting costs and sustain output amid labor-intensive colonial economies. In , commercial cultivation commenced in the 1860s, spreading northward from to , where ratooning became a standard practice with farmers harvesting several regrowth cycles before rotating to cover crops like . The shift from experimental to large-scale production was fueled by domestic needs and export opportunities, enabling multi-ratoon systems to align with the 12-15 month and support over 70 small mills by the late . In the 20th century, ratooning was increasingly incorporated into mechanized farming systems in the and , enhancing efficiency while necessitating research into long-term . In the , particularly , post-World War II advancements in chopper harvesters introduced challenges like post-harvest residue accumulation, which reduced subsequent ratoon yields by 10-20% due to cooler, saturated soils inhibiting growth; studies from this era emphasized timely residue removal—ideally within 7-10 days post-harvest or during winter —to maintain ratoon viability. In , mechanized harvesting rose from 24% in 2007-2008 to over 88% by 2019-2020, predominantly in the flatter Central-South region, where ratooning cycles of 4-5 years became integral to low-cost production; breeding programs, such as those by RIDESA, developed varieties like RB867515 optimized for mechanized systems, addressing issues like and straw retention from unburned fields. Mechanized harvesting has further increased, reaching over 95% in the Center-South region as of 2025. These developments reflected a global trend toward 80-90% ratoon reliance in high-output nations like , contrasting with shorter cycles elsewhere. By the early 21st century up to 2025, ratooning adoption has grown notably in , especially among smallholder farmers in , while has differentially influenced its uptake in tropical versus subtropical zones. In western and Nyanza regions, where supports around 170,000 smallholder households, ratooning has gained traction for its ability to cut production costs by up to 30% through avoided replanting and labor expenses, allowing 2-3 cycles with proper fertilization and weeding before replanting. This aligns with broader African trends toward sustainable intensification amid land scarcity, mirroring practices in major producers like (over 50% ratoon area) and (50-70%). Globally, ratoon crops account for 50-55% of production in tropical areas and 40-45% in subtropical areas. poses varying risks, with tropical zones experiencing heightened pest and pressures—such as smut and ratoon stunting exacerbated by dry spells—while subtropical areas benefit from adaptive breeding for resilient varieties and integrated management to counter erratic rainfall and temperatures. Studies from 2020-2024 highlight the need for precision tools like sensors for early detection to sustain ratooning under these conditions.

Sugarcane Applications

Assessing Ratooning Potential

Assessing the potential for successful ratooning in sugarcane varieties involves evaluating genetic traits that promote vigorous regrowth from stubble, as these determine the crop's ability to produce multiple harvests without replanting. Key genetic indicators include high production, characterized by a rapid tillering rate and a large number of effective tillers, which supports dense stand establishment in ratoon crops. Strong vigor, evidenced by deep systems, abundant underground buds, and persistent root structures, enhances and uptake for sustained regrowth. Additionally, resistance to diseases such as smut (caused by Sporisorium scitamineum) and pests like borers is crucial, as susceptibility accelerates stubble decline and reduces ratoon longevity. Varieties exhibiting these traits, such as Co 0238 (Karan 4) in , demonstrate superior ratooning performance, contributing to higher yields over multiple cycles in subtropical regions. Field assessment techniques focus on post-harvest stubble characteristics to predict ratoon success. Stubble height is measured immediately after harvest, with optimal levels (typically 5-10 cm) minimizing bud damage and mortality while preserving root integrity for regrowth. Bud germination rate is evaluated by monitoring the percentage of viable buds sprouting within 30-45 days, targeting rates above 70% to ensure adequate stand establishment. Initial sprout density, counted as shoots per stool or per unit area, indicates early vigor; densities exceeding 10-15 sprouts per linear meter are associated with higher millable cane populations and yields. These metrics, often assessed in variety trials, allow breeders to select clones with low stubble mortality and rapid tillering. Environmental factors significantly influence ratooning potential, particularly soil conditions and pre-harvest management. Loamy soils with good drainage and content are preferred, as they support proliferation and reduce waterlogging risks that hinder bud sprouting. Optimal ranges from 6.0 to 7.5, facilitating availability and minimizing issues that impair stubble health. Pre-harvest conditions, such as harvesting during periods with soil temperatures above 20°C, promote faster and reduce cold-induced in buds. A key quantitative tool for evaluation is the ratoon index, defined as the ratio of ratoon to cane yield (often averaged across cycles), where values above 0.8 indicate strong potential for economic ratooning over 2-3 cycles.

Growth Differences: Ratoon vs. Plant Crop

Ratoon crops exhibit distinct physiological differences from initial crops, primarily due to their reliance on pre-existing systems and stubble buds rather than seed-based establishment. In ratoon crops, growth draws from established reserves accumulated during the prior cycle, enabling faster initial and uptake but resulting in shallower expansion as new roots primarily emerge from the upper stubble layers, limiting deep penetration. In contrast, crops initiate from setts or seedcane, requiring substantial energy for developing a comprehensive network, including deeper permanent roots that enhance long-term anchorage and resource access. This shallower rooting in ratoons can constrain later-season compared to the more extensive root depth in crops. Yield patterns in ratoon crops typically show a progressive decline relative to the crop, with the first ratoon yielding 70-90% of the crop's output in optimal tropical conditions, often reflecting a 10-30% reduction in cane tonnage. For instance, in subtropical Indian conditions, crops may achieve 65-75 t/ha, while first ratoons often drop to 30-35 t/ha (approximately 46-54% of yield) due to cold stress, depletion, and management challenges. By the third ratoon, yields can fall to approximately 50% of the crop due to cumulative exhaustion of reserves and diminished stalk vigor, though high-ratooning varieties mitigate this through sustained stalk numbers. Developmental stages in ratoons feature accelerated early progress, particularly in tillering, driven by pre-formed buds on residual stubble that enable quicker shoot . Tillering in ratoons initiates more rapidly and synchronously, with peak populations reached in about 60 days after ratooning, compared to 120 days after for crops, where is more prolonged and asynchronous. This compressed tillering phase in ratoons—often shortened to 60 days from 120 days in crops—supports higher initial shoot densities but higher subsequent mortality rates, up to 51% in narrow rows, versus 30% in crops. Overall, these dynamics contribute to vigorous early vegetative growth in ratoons, though sustained hinges on varietal traits and environmental factors.

Earlier Ripening in Ratoons

Ratoons in achieve earlier than plant crops due to inherent biological advantages that streamline development. The pre-existing vascular systems and extensive root networks established during the plant crop phase enable efficient transport of water, nutrients, and photosynthates, bypassing the energy-intensive establishment of new root systems from scratch. Additionally, nutrient reserves accumulated in the stubble and rhizomes from the prior serve as an immediate carbon and energy source, allowing ratoon shoots to transition rapidly from to active vegetative growth and subsequent reproductive phases, such as internode elongation and accumulation. This biological head start significantly shortens the overall maturation period for ratoons, typically requiring 10-12 months to reach harvestable ripeness compared to 12-18 months for plant crops. Environmental factors further accelerate this process by leveraging post-harvest conditions. Ratoons often emerge during seasons with progressively shorter day lengths in subtropical regions, which trigger earlier initiation of ripening signals like reduced vegetative growth and enhanced synthesis; meanwhile, the carryover of accumulated heat units ( sums) from the plant crop optimizes requirements, enabling faster progression through growth stages without the full accumulation needed for seedlings. Hormonal regulation in the stubble reinforces this rapid ripening. Higher concentrations of (indole-3-acetic acid, IAA) promote cell elongation and basal germination, driving swift cane extension in ratoon-competent varieties. Similarly, elevated levels, particularly GA3, stimulate internode expansion and enhance sink capacity in stalks, facilitating quicker sugar accumulation by upregulating genes involved in transport and storage. These hormonal dynamics, observed in physiological studies of ratoon regrowth, underscore the molecular basis for the accelerated timeline.

Impact of Cold Harvests

Harvesting sugarcane under low-temperature conditions, particularly in subtropical regions, poses significant risks to the establishment and productivity of subsequent ratoon crops by damaging residual stubble and buds. Temperatures below 20°C during the harvest period can severely inhibit bud sprouting and overall regrowth, as sugarcane requires warmer conditions for optimal physiological processes in the ratoon phase. Frost events, occurring at temperatures of 1–2°C, exacerbate this damage by killing meristem tissues and causing desiccation of the stubble, which further compromises the structural integrity needed for new shoot emergence. While exact thresholds vary by variety and location, exposure below 8–10°C has been shown to hinder critical post-harvest recovery, leading to germination rates that are substantially lower than under warmer conditions. These cold-induced effects manifest physiologically through impaired accumulation of photosynthetic reserves in the stubble, which are essential for initial ratoon tillering and rejuvenation. Low temperatures reduce and expansion, resulting in weakened systems that limit and uptake for the emerging . Consequently, ratoons exhibit sparse tillering—fewer shoots per unit area—and diminished sucrose accumulation in stalks, directly lowering overall cane quality and recoverable content. Ratoon growth relies on these stored reserves from the previous , and cold stress disrupts their mobilization, amplifying the yield decline across cycles. In subtropical , winter harvests coinciding with low s (often below 20°C) drastically reduce ratoon yields; as of 2008, national averages showed ratoon productivity at approximately 58 tonnes per compared to 85 tonnes per for cane—a loss of around 32%—though overall yields have improved to about 79 t/ha by 2024. Similar challenges occur in parts of , where cold winter conditions during harvest impair stubble viability and contribute to 20–25% lower ratoon yields relative to optimal timing, as documented in regional studies on extremes. These impacts highlight the vulnerability of ratooning systems in areas prone to seasonal chills, where yield losses of 20–40% are common without adaptive measures.

Management Practices

Effective management of sugarcane ratoon crops begins immediately after the plant cane to promote vigorous regrowth from the stubble. Stubble should be shaved to a height of 3-5 cm using sharp blades or specialized shavers to stimulate sprouting and tillering while minimizing damage to the underground buds and . This low cutting height, typically achieved within one week of , enhances development and reduces the risk of in subsequent cycles. Trash and crop residues must be promptly removed or incorporated into the via rotavation to prevent the buildup of pests, diseases, and fungal pathogens, thereby improving and reducing interference with emerging shoots. timing is critical, with plant cane cut close to the ground when conditions favor stubble sprouting, ideally avoiding periods of impending stress to ensure optimal regrowth initiation. Nutrient management for ratoons requires adjustments to account for depleted reserves and the crop's higher demand for rapid establishment. applications are typically 20-30% higher than for plant cane, at rates of 200-250 kg N/ha, to support tillering and accumulation, with the majority applied in the first 60 days post-harvest. These doses are split: an initial one-third immediately after stubble shaving, followed by top-dressing at 30 and 60 days, often combined with off-barring to incorporate fertilizers efficiently. and supplements are also essential, tailored to tests, to maintain balance and prevent deficiencies that could limit ratoon longevity. schedules must sustain at 60-70% of during the critical early growth phase, with applications every 7-10 days via furrow or drip systems to avoid waterlogging while promoting deep rooting. Alternate furrow can reduce water use by up to 50% without compromising yields, particularly in the tillering stage (36-100 days after harvest). Pest and disease control in ratoon crops emphasizes preventive cultural practices integrated with targeted chemical interventions to mitigate buildup over cycles. Trash removal and stubble management reduce habitats for soil-borne pests like wireworms and beetles, while monitoring for sugarcane borers prompts applications (e.g., 0.033 lbs/acre Asana XL) when infestation reaches 5% of stalks, typically from mid-June to . For diseases such as (caused by falcatum), rogue and burn affected clumps immediately, and apply targeted fungicides like triadimefon (40 g/20 L water) as a sett treatment or foliar spray if symptoms appear early in the ratoon. To prevent disease accumulation, limit ratooning to 2-3 cycles before implementing with non-hosts like or , which breaks cycles and restores . Variety selection during initial planting, favoring those with high ratooning potential, further supports these practices by reducing susceptibility to common threats.

Specific Examples

In , multi-ratoon systems under organic and conventional have demonstrated sustainable yields averaging 75-80 tons per across three cycles, with the first ratoon often reaching up to 80.8 tons per when using sulphitation press mud cake combined with biofertilizers; as of 2024, new varieties achieve average cane yields of 76-83 t/ha with improved ratooning. These outcomes highlight the role of integrated nutrient practices in maintaining productivity over successive harvests in subtropical regions. In , mechanized ratooning benefits from technologies, including GPS-RTK guidance systems that enhance harvesting accuracy and reduce crop damage through controlled traffic farming, thereby supporting efficient large-scale operations. Automatic steering integrated with GPS has improved operational efficiency in harvesters, minimizing in ratoon fields. The variety CP 88-1762, developed for Florida's organic soils, exhibits good ratooning ability, enabling multiple cycles (typically up to three or more with appropriate management) while maintaining high and tillering. Its robust stubbling supports continued production in rotation systems despite challenges like susceptibility to orange . In , smallholder farmers practicing ratooning have achieved cost reductions of up to 25-30% per cycle, primarily through savings on labor, seed cane, and land preparation, as reported in recent agricultural assessments. These savings are particularly impactful in Western Kenya and Nyanza regions, where ratooning aligns with limited resource availability.

Other Crop Applications

In Rice

In rice cultivation, ratooning involves harvesting the main crop at a stubble height of 20-30 cm above the surface, which preserves sufficient nodes for the regrowth of secondary tillers from the remaining stubble. This technique leverages the natural tillering process, where axillary buds at the base develop into productive following the harvest. It is particularly effective with hybrid varieties like DRR Dhan 44, which demonstrate strong ratooning potential due to their robust tiller regeneration and yield stability in subsequent cycles. The ratoon crop generally achieves yields of 40-60% relative to the main crop, with maturation occurring in 60-80 days under optimal conditions. This shorter cycle allows for rapid turnaround in paddy systems, making ratooning advantageous in flood-prone regions of , such as parts of southern and , where seasonal water availability supports quick regrowth without extensive replanting. Key challenges in rice ratooning include precise water management to maintain adequate moisture for tiller emergence while preventing excessive flooding that could lead to lodging of the developing shoots. In , where ratoon rice has gained prominence, the practice covers approximately 1 million hectares as of 2025, contributing significantly to national rice production through recent expansions, with plans to increase the area by an additional 666,000 hectares by 2030.

In Cotton

Ratooning in cotton (Gossypium spp.) involves cutting back the plants after the main harvest to encourage regrowth from basal buds and roots, allowing for multiple cycles from a single planting. This practice is particularly used in tropical and subtropical regions such as China and India, where it supports perennial cropping systems that reduce labor and planting costs while maintaining yields over 2-3 seasons. However, challenges include increased susceptibility to pests, diseases, and reduced fiber quality in later cycles, necessitating careful variety selection and management. Ratoon cotton systems have been explored for sustainable production, especially in hybrid breeding to preserve male sterility.

In Sorghum and Cereals

Ratooning in , a key dryland cereal, involves harvesting the primary crop while leaving basal stubble at 15-20 cm height to stimulate regrowth from crown buds and tillers, enabling subsequent cycles without replanting. This technique is particularly adapted to arid and semi-arid environments, where sorghum's inherent allows efficient water use during regrowth phases. In regions like and , where sorghum serves as a staple for grain and , ratooning supports multiple harvests in rainfed systems by leveraging residual and nutrients. Typically, 2-3 ratoon cycles are feasible, with the first ratoon yielding 50-70% of the main 's output, depending on application and planting density. For instance, studies show ratoon yields averaging 50-58% of main levels under optimized conditions, such as 255 kg/ha , which enhances by up to 45%. Drought-tolerant varieties like IS 2205, an elite line from ICRISAT, exhibit strong regrowth potential and resistance to stresses like stem borers, making them ideal for these cycles in low-rainfall areas of and . Beyond , ratooning applies to other cereals like and millet primarily for production in semi-arid zones. In the Midwest, where variable precipitation challenges annual cropping, ratooning exploits tillering for additional green after grain harvest, yielding supplementary in dry seasons. Similarly, , valued for its rapid regrowth and low water needs, is ratooned for multiple cuts in semi-arid Midwest fields, providing up to one-third more dry matter than single-harvest systems.

In Perennials and Vegetables

In perennial fruit crops like bananas, ratooning is practiced by harvesting the main bunch and then selecting a single vigorous sword sucker from the base while removing all competing suckers through desuckering; the harvested pseudostem is cut back near the base to encourage regrowth from the underground rhizome. This allows the same stool to produce multiple successive cycles, typically three to five ratoons, before replanting is required due to declining vigor or disease buildup. The technique promotes efficient resource allocation to the selected sucker, resulting in uniform bunch development and sustained yields over 3-4 years in commercial systems. Pineapple ratooning similarly relies on vegetative from suckers or slips emerging from the stubble after the initial plant crop is harvested around 18-20 months post-planting. Growers apply chemical forcing agents, such as , 5-7 months after harvest to synchronize flowering in the first ratoon, with a second cycle possible under optimal and low pest pressure; the process typically yields 2-3 crops total over 32-46 months. Ratoon fruits are generally smaller in size but exhibit enhanced , reduced acidity, and greater aroma compared to the plant crop. Among perennial vegetables, asparagus demonstrates a natural form of ratooning, with edible spears emerging annually from established crowns after the previous season's harvest; plants remain productive for 15-20 years following a 2-3 year establishment phase, during which ferns develop to nourish the root system. Rhubarb follows a comparable pattern, regrowing new stalks each spring from its perennial crown after cutting the previous year's growth, sustaining harvests for 8-10 years or longer with division every 4-5 years to prevent overcrowding. In both cases, the regrowth stems from stored energy in the underground crowns, enabling long-term productivity without replanting. Experimental ratooning in potatoes involves hilling soil around stubble after the main harvest to stimulate basal shoot regrowth for a secondary crop, often tested in rotation systems to extend yield in short-season environments; however, adoption remains limited due to increased risks of tuber-borne diseases and reduced tuber quality in the ratoon generation. Overall, these practices in perennials and vegetables extend orchard and bed productivity, with banana systems achieving up to 183 metric tons per hectare over 40 months through optimized sucker management, thereby enhancing resource efficiency in established plantings.

Advantages and Challenges

Benefits

Ratooning offers significant economic advantages in production by reducing costs associated with planting, land preparation, and labor, typically saving 25-30% compared to establishing a new plant crop. These savings arise because the existing supports regrowth without the need for replanting seed cane or extensive soil tillage, allowing farmers to allocate resources more efficiently. Additionally, ratoon crops mature faster than plant crops, often reaching harvest readiness 2-3 months earlier—requiring around 295 days under versus 12-18 months for initial planting—which improves through quicker returns on . From an agronomic perspective, ratooning preserves the established root network, enhancing and retention while minimizing disturbance that could compact . This practice reduces by maintaining ground cover and limiting , which otherwise exposes to wind and degradation. Furthermore, the intact improves infiltration and holding capacity in established fields, potentially lowering requirements and promoting more efficient use overall. Environmentally, ratooning decreases the demand for inputs like fertilizers and pesticides, thereby reducing chemical runoff into waterways and associated non-point source . The perennial nature of ratoon systems also supports greater in through persistent and reduced , which can exceed that of annual cropping by maintaining higher soil organic carbon levels compared to systems requiring full replanting each cycle.

Limitations and Risks

One of the primary limitations of ratooning is the progressive decline in yield across successive cycles, often amounting to 20-40% reductions depending on variety and environmental conditions, attributed to depletion and the buildup of pests and pathogens. In , this exhaustion of essential nutrients like and , coupled with increased pest pressure from stem borers and systems weakened by repeated harvesting, restricts profitable production to typically 3-4 ratoon cycles before yields become uneconomical. Health risks further compound these challenges, as ratoon crops exhibit heightened susceptibility to diseases such as smut (Sporisorium scitamineum), with incidence and severity often approaching 100% in susceptible varieties by the second ratoon due to persistent inoculum in stubble and . Soil exhaustion from continuous cropping exacerbates this vulnerability, leading to reduced , acidification, and proliferation, necessitating after limited cycles to restore and break disease cycles. Additional challenges include elevated management demands for nutrient supplementation and to offset declines, alongside that limits ratooning viability in temperate zones through cold-induced damage to regrowth buds and roots. Recent 2025 research underscores how global warming may intensify these risks via erratic weather patterns and stress on ratoon stands despite overall warming benefits in subtropical areas.

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