Ratoon Crop Research Articles

The general ratooning ability of rice yield‐related traits: A meta‐analysis

AbstractNumerous studies have attempted to pinpoint certain traits of rice varieties linked with great ratooning ability that may be used in cultural practice. However, both genetic and environmental variables affect rice's capacity for ratooning. We are able to measure the innovative ratooning ability that affects the decline in ratoon yield using the agronomic features of the main crop and ratoon rice in our global database for a meta‐analysis, drawn from 51 experiments in 14 countries. We discovered that changes in cultivar yield and maturity features, cropping location, and nitrogen fertilizer treatment may all affect a plant's capacity to tiller. On the other hand, the growth duration ratoon ability was less responsive to variations in cultivars and cropping location. We also found that ratooning changes the plant architecture for yield generation from bigger spikelets with fewer panicles to fewer spikelets (dropping 48%) with larger panicles (increasing 19%). We came to the conclusion based on our research that the decreased yield in ratoon crops may be caused by fast ear emergence and aggressive tillering, which negatively influence stem elongation, panicle differentiation, and a lack of nutrition, resulting in fewer spikelets (panicle−1). The present data are thoroughly summarized and analyzed in this research, which also clarifies the lack of knowledge around the characteristics that affect ratoon rice crop production.

Impact of soil type and harvest season on the ratooning ability of sugarcane varieties

Summary Sugarcane varieties differ in their ratooning ability (RA), and it is hypothesized that soil types and harvest seasons impact varieties’ RA. However, the effects of these factors on varieties’ RA remain unclear. This study aimed to assess the RA of different commercial sugarcane varieties (NCo376, N19, N23, N25, and N36), and establish the effects of soils and seasons on ratoon yields of these varieties in Eswatini. Fifteen years data on tons cane per ha per annum (TCHA) and tons sucrose per ha per annum (TSHA) achieved by plant cane and seven ratoon crops were collected from four commercial growers and analysed using linear regression models. The varieties significantly differed in RA. Variety N25, which had the highest plant cane yields (121.3 TCHA and 16.7 TSHA), had the sharpest yield decline over ratoon crops (–2.74 TCHA and −0.33 TSHA), suggesting that this variety is more suitable for short crop cycles. Variety N36 had second highest plant cane yields (111.7 TCHA and 16.4 TSHA) and a lower ratoon yield decline (–1.38 TCHA and −0.16 TSHA) than N25, suggesting that it is suitable for longer ratoon crop cycles. While soil type and harvest season significantly affected the relative yields of varieties, they did not significantly impact their RA, indicating that differences in varieties’ RA were driven by genotype and were relatively stable across environments. This suggests that tests to assess the adaptability of varieties should be conducted in multiple environments, while testing the RA of varieties may be conducted in fewer environments.

Effect of Change of Agronomic Practices on Nutritive Value of Hybrid Fodder Sorghum Cultivated in Lowland Paddy Fields of the Dry Zone of Sri Lanka

This study was conducted to investigate the effect of low fertilizer rate and irrigation along with increased plant density on nutritive value of hybrid fodder sorghum cultivated in lowland fallowed paddy fields in dry zone during May to September. Seeds were sown in Yala season and continued as a ratoon crop to inter-monsoonal (Third) season. Four agronomic management packages (AMP1, AMP2, AMP3 and AMP4), which differ in fertilizer application rates, plant spacing, and irrigation intervals were tested with two fodder sorghum varieties (SX-17 and Dairygreen) in a split-plot design. The initial and first ratoon crops were harvested at dough grain stage. High fertilizer rate in combination with short irrigation interval, resulted in high (P<0.05) crude protein content in the initial harvest. AMP2 and AMP4 produced equally high (P<0.05) total dry matter yield (DMY) for SX-17 (24.7 and 20.9 MT/ha, respectively) and Dairygreen (27.7 and 25.7 MT/ha, respectively) varieties. Total digestible organic matter, crude protein and metabolizable energy yields were higher under AMP2 and AMP4 compared to other two packages for both varieties. Nutritive value was high in SX-17 under AMP1 for ratoon crop. In conclusion, AMP4 with plant spacing of 45 x 15 cm, low fertilizer rate (338-47-28 kg/ha, urea-TSP-MOP) and extended irrigation interval, could be recommended for cultivation of hybrid fodder sorghum in lowland paddy fields in the dry zone during Yala season. However, for cultivating SX-17 targeting to produce fodder with high nutritive level, AMP1 with spacing of 45 x 30 cm, high fertilizer rate (400-62-37 kg/ha of urea-TSP-MOP) and frequent irrigation could be recommended.

Flooding tolerance of sugarcane genotypes under recurring floods in plant and ratoon crops

Flooding tolerance of sugarcane genotypes under recurring floods in plant and ratoon crops

Developing Biocontrol Strategies for the Management of Set rot Disease of Sugarcane under Wider Row Planting

Sugarcane (Saccharum officinarum L.) is one of the economically valuable agricultural crops grown worldwide in tropical and subtropical areas mainly for their sugar source. Among the 110 sugarcane cultivated countries, India and Brazil contribute half of global production [1]. During the period of last five decades the production, productivity and sugarcane recovery has also shown remarkable resilience in productivity growth rate. One of the reasons for the low productivity and recovery is increasing incidence of insect pests and diseases. An ecologically friendly alternative to these problems is biological control using rhizobacteria and their metabolic products [2]. In order to develop a technology capsule Surveys and surveillance were conducted in sugarcane fields both in plant and ratoon crops distributed in Orthanadu and Vallam block in New Cauvery delta area of Thanjavur dictrict during three consecutive years 2019- 22 with an objective to assess the incidence of sett rot, red rot and smut in New Cauvery delta area of Thanjavur dictrict. Fortnightly fixed plot observation was taken. The Maximium and minimum temperature, RH and quantity of rain and rainy days also recorded daily and consolidated on monthly basis and weather parameters were correlated with the incidence of disease. The results revealed that the maximum incidence sett rot negatively correlated with temperature. Similarly the number of rainy days and rainfall is positively correlated (r = 0.7523) with incidence of sett rot. For managing sett rot disease of sugarcane through biological approach, studies were conducted on biocontrol agents viz., Trichoderma asperellum (TNAU), Bacillus subtilis (TNAU), Chaetomium globosum (Cg6) with fungicide check propiconozole 0.1%. Among the treatment, highest millable cane (91,080/ha) and yield (91.39 tonnes / ha) and sugar yield ( 10.63 tonnes/ha) were recorded in M1- (Single bud treated with Trichoderma asperellum (TNAU)@ 4 g l-1 + soil application @ 2.5 kg ha-1) followed by M2- (Single bud treated with Bacillus subtilis (TNAU)@ 10 g l-1 + soil application @ 2.5 kg ha-1) in which, the cane yield of 88.54 tonnes/ha and sugar yield of 10.68 tonnes/ha were recorded. This study provides a technology capsule for the management of important disease of sugarcane.

Effect of Plant Nutrients on Fruit Yield and Quality of Cavendish Banana (Musa sp.) cv. ‘Grand Naine’

A field experiment was conducted to evaluate the effect of plant nutrients on yield and fruit quality of ‘Grand Naine’ banana under alkaline soil conditions for the two cropping seasons 2020-2021 and 2021-2022 at Directorate of Agricultural Research (DoAR), Khajura. The trial was laid out in a randomized complete block design consisting of seven treatments replicated three times having four plants in an experimental plot. Planting of tissue culture banana was done at 2×2 m spacing on 4th July 2020 and suckers selected from the same plant on the same date were taken as the first ratoon crop. Farmyard manure was applied at four, chemical fertilizers at six, and micronutrients at three installments. The pooled results revealed that the longest bunch (114.30 cm), the highest number of hands (10.08) and finger number per bunch (185.80) and second hand (21.50), the heaviest bunch (25.74 kg) and second-hand weight (3.28 kg), the highest finger length (21.08 cm), diameter (3.85 cm) and weight (156.20 g) and bunch yield (64.35 mt/ha), the highest TSS (20.20%), TSS: TA ratio (47.10) and total sugar (12.55%) and the lowest TA (0.43%) were registered in T3 (20 kg FYM, 250:250:350 g NPK along with foliar spray of four types of micronutrients viz. Zn, Fe, Cu and B at 3rd 5th and 7th months of planting. Hence, from the study banana growers are recommended to use FYM, chemical fertilizers along with a foliar spray of micronutrients, at least three times in the vegetative growth stage of bananas for higher yield and improved quality of fruits.

Total Factor Productivity Growth and Changing Cost Structure of Sugarcane in Gujarat, India

Aims: 
 
 To estimate the growth of input, output indices and total factor productivity of sugarcane in Gujarat
 To estimate the changing cost structure of sugarcane
 
 Place and Duration of Study: Department of Agricultural Economics, Junagadh Agricultural University (between June 2018 and July 2020).
 Methodology: This paper has estimated the growth in total factor productivity of sugarcane crop using Tornqvist Theil index and growth trends in cost structure of sugarcane crop in Gujarat.
 Results: The results showed that the growth rate of TFP indices of sugarcane planted crop and ratoon crop were negative about -0.86 and -0.31 per cent per annum, respectively. Negative TFP growth resulted due to a relatively faster rate of total input growth than total output growth. in the total cost of cultivation of sugarcane, the cost share of human labour, irrigation and miscellaneous in Gujarat has shown an increasing trend. while, rental value of land showing declining trend. 
 Conclusion: Study suggested that technological gains have not been experienced in this crop needs concentrated efforts to bridge extension gap and further research to evolve concrete strains, resistant to pest and diseases which reduce the real cost of production.

Effect of crop management and climatic factors on weed control in sugarcane intercropping systems

ContextCover crops in intercropping systems have a high potential to manage weeds in tropical agroecosystems as an herbicide alternative. However, it still needs to be better investigated in sugarcane cropping systems. ObjectiveThis study assesses the weed control ability of cover crops in sugarcane intercropping systems depending on crop management and climate in tropical conditions. MethodsThis study was based on a set of eight experiments, including ten cover crop species, performed from 2012 to 2021 in three areas in Reunion Island (France) and comparing three inter-row management treatments: i) chemical weed control, ii) cover crops sown in the inter-row, and iii) low weed control. Mean weed and cover crop ground cover were measured during the entire crop cycle, and the complementary weed management practices (herbicide, manual weeding) were also recorded. Sugarcane yield and crop management were evaluated to assess the economic impact of a change in practice. ResultsMean weed ground cover was reduced by 51 % in the cover crop and chemical treatments compared to low control. Additionally, the cover crop treatment had an herbicide treatment frequency index lower by 37 % compared to chemical treatment but a higher number of manual weedings. In all treatments, weed cover increased with rainfall and temperature. In the cover crop treatment, a structural equation modeling approach allowed us to highlight the influence of cover crop (sowing date and species) and sugarcane management (crop cycle - plant or ratoon crop) on weed cover. Weed cover decreased with an increase in cover crop ground cover, which was higher for the early sowing date. Additionally, weed cover was lower in ratoon crops than plant crops but increased over time since intercropping was implemented. Finally, sugarcane yield was lower by 6 % in cover crop treatment compared to chemical treatment. The change in operating costs and revenues between these crop management induced a decrease in profits in intercropping compared to chemical cropping systems, variable according to the degree of mechanization. ConclusionsThis study highlights the predominance of management factors, compared with climate, to explain the effectiveness of weed control in sugarcane intercropping systems. ImplicationsDue to the change in weed cover over time, there is a need to assess the long-term sustainability of this practice and the potential change in weed communities.

Impact of residue retention and nutrient management on carbon sequestration, soil biological properties, and yield in multi-ratoon sugarcane

Sequestration of carbon (C) in arable cropping systems is considered one of the potential climate change mitigation strategies. In this context, assessing the potential of sugarcane cropping systems should be a priority, as it leaves substantial amounts of recyclable residues essential for maintaining soil organic carbon (SOC), improving soil health, and strengthening overall resources. We evaluated the impacts of residue retention and nutrient management practices on SOC and its pools, storage, soil biology, and yield in a multi-ratooning sugarcane system. A field experiment was conducted in the split-plot design with residue burning (RB) and residue retention (RR) as the main plot treatments and three nutrient management practices, that is, 25% of the recommended dose of fertilizers (RDF, i.e., 300:150:150 kg of N, P2O5, and K2O kg ha−1, respectively) as basal + 75% through fertigation (N1); 50% of RDF as basal + 50% through fertigation (N2); and 75% of RDF as basal + 25% through fertigation (N3) as subplot treatments in ratoon sugarcane. Soil samples were collected initially and after 6 years of multi-ratooning (one plant and four ratoon crops) from a soil depth of 0–30 cm. The results indicated that RR plots had 21% higher total SOC with 42, 47, 17, and 13% higher very labile, labile, less labile, and non-labile C pools, respectively, than RB plots (P < 0.05). RR also had a higher lability and recalcitrant index than RB. Of the total SOC stock, the contribution of passive pools was higher (72–75%) than active pools. Significantly higher dehydrogenase activity (DHA) (86%), alkaline phosphatase activity (APA) (16%), and ß-glucosidase activity (BGA) (22%) were observed in RR plots as compared to RB plots, whereas for nutrient management practices, it followed the order of N2 > N3> N1. Microbial counts also followed the same trend as that of enzyme activities. Residue retention practices reported higher C sequestration (0.68 Mg C ha−1 yr−1), carbon retention efficiency (37%), and yield (38%) with a potential to reduce GHG emissions by 2.72 Mg CO2 ha−1 yr−1 as compared to traditional practices. Residue retention and 50–75% RDF as basal is recommended for higher soil C retention and soil biology for sustained sugarcane productivity.

Reducing cadmium accumulation and increasing grain yield with proper timing of flood irrigation in the second season of ratoon rice

Context or problemThe second season of ratoon rice (ratoon crop, RC) exhibits a high risk of cadmium (Cd) contamination in grains, requiring effective irrigation management strategies to reduce its grain Cd concentration. Objective or research questionThis study aimed to determine the crucial growing period for Cd accumulation and provide irrigation recommendations for reducing grain Cd concentrations with limited water input in the ratoon season. MethodsA two-year field experiment was conducted in Hubei province, central China. The entire growth duration of RC was divided into three short periods: from harvest of the main crop (HM) to initial heading of RC (IH), from IH to full heading of RC (FH), and from FH to maturity of RC (MR). During each growth period of RC, two water regimes (flooded and rainfed) were established. Therefore, there were a total of eight water treatment combinations in this experiment, using a randomized complete block design. Two hybrid varieties were planted in this study. ResultsAcross years, varieties and treatments, the grain Cd concentration of RC ranged from 27.8 to 314.1 µg kg−1, with 37.5% of rice samples exceeding the national food safety standard for Cd (200 µg kg−1). RC grown under continuous flooding conditions produced the lowest grain Cd concentration and highest grain yield. Compared with rainfed conditions, maintaining flooded conditions from HM to IH, from IH to FH, and from FH to MR resulted in decreases of 28.4%, 62.7%, and 12.0% in grain Cd concentration and decreases of 25.5%, 49.9%, and 16.3% in total Cd accumulation at maturity, respectively. RC took up the most Cd during the period from IH to FH under rainfed conditions; however, maintaining flooded conditions reduced Cd uptake by 95.4% during this period. Moreover, flooding from IH to FH had the most positive impact on the grain yield of RC, with an increase of 8.1% compared with rainfed conditions. ConclusionsMaintaining flooded conditions from initial to full heading for 15–18 days was not only effective in reducing grain Cd concentration but also beneficial for improving grain yield in the ratoon season. Implications and significanceThis study clarified the effects of water management during different growing periods on Cd accumulation and grain yield in the ratoon season. We emphasized the necessity of flooding during heading period to control Cd accumulation in RC grains, especially in areas with limited water resources and high soil Cd concentration.

Analysis of sugarcane × Saccharum spontaneum progeny for sugar and biomass traits

AbstractSugarcane production benefitted from useful genes imparted from Saccharum spontaneum L. Interspecific hybrids were evaluated for sugar and biomass traits in three environments, including two plants and one ratoon crop. The objective was to estimate genetic parameters for traits in this population and to develop appropriate breeding strategies and germplasm for use in variety development in both the sugar and bioenergy industries. Heritability was highest with all three environments considered; however, the increase was minimal compared with estimates from the first ratoon crop, suggesting resources will be better spent selecting in the first ratoon crop. Significant differences (p < 0.05) found among families for sucrose content‐related traits warrant selecting first among families before selecting among genotypes within families for these traits. The same was not true for cane yield and its components. Heritability was low to moderate (> 0.3 < 0.47) for cane yield and its components and high (> 0.7) for all other traits, suggesting early selection in small plots could emphasize sucrose content‐related traits. Selecting intensely for a highly heritable trait in one stage can influence genetic variation of another trait in subsequent stages. Therefore, multivariate selection methods were employed that identified groups of genotypes with characteristics distinct to both industries. The S. spontaneum parents dominated trait variation in the hybrid population. Consequently, although genotypes with potential for the sugar industry would have to undergo rounds of backcrossing to recover good sugar characteristics, genotypes with immediate potential in the bioenergy industry were easily identified in this population.

Lignocellulosic Composition Not Associated with Stem Borer Resistance in Select Louisiana Sugarcane Cultivars

The two most economically damaging insect pests of sugarcane in Louisiana are the sugarcane borer (SCB) and the newly invasive Mexican rice borer (MRB), both of which can be managed in part with cultivar resistance. High stalk fiber levels is a well-documented aspect of stem borer resistance but is inversely correlated with recoverable sugar levels. However, lignocellulosic components such as hemicellulose, cellulose, and lignin are associated with resistance to other borer species in poaceous crops, potentially indicating mechanisms that may provide resistance without substantial trade-offs in yield. The goal of this study was to determine whether lignocellulosic composition varied among four cultivars—HoCP 85-845, HoCP 04-838, Ho 07-613, and HoCP 00-950—selected based on known variation in SCB and MRB resistance and total fiber content. We estimated lignocellulosic composition as well as Brix throughout the growing season and the total stalk fiber and recoverable sugar content at harvest for both plant cane and first ratoon crop years. We found that the Brix content throughout the growing season, as well as total fiber and sugar content at harvest, were significantly associated with the cultivar, aligning with previously documented trends in borer resistance (i.e., higher Brix and lower total fiber indicate a more susceptible cultivar). While lignocellulosic composition during the growing season was not associated with cultivar or resistance to either borer species, it was significantly impacted by sampling month and crop year. These data indicate the potential influence of alternative resistance mechanisms and interactions with abiotic conditions.

Identification of resistance to Sugarcane mosaic virus, Sugarcane streak mosaic virus, and Sugarcane bacilliform virus in new elite sugarcane accessions in India.

Sugarcane mosaic and leaf fleck diseases are significant viral diseases affecting sugarcane crops in India. The use of resistant sugarcane varieties is considered the most economical and effective approach to manage viral diseases, especially in vegetatively propagated crops such as sugarcane. Sugarcane mosaic virus (SCMV) and Sugarcane streak mosaic virus (SCSMV) are the primary pathogens responsible for mosaic disease in sugarcane-growing regions of India. Sugarcane bacilliform virus (SCBV), causing leaf fleck disease, is also often found in mixed infections with mosaic symptoms. The study aimed to identify new sources of resistance by screening sugarcane germplasm for resistance to SCMV, SCSMV, and SCBV. The screening was carried out under high inoculum using the infector row method in both plant and ratoon crops. Out of 129 genotypes tested, only 8 were found to be free of mosaic viruses, indicating a rare occurrence of resistant sources. The study revealed that mosaic disease is widespread, with nearly 95% of tested varieties/genotypes being infected with mosaic viruses. SCMV, SCSMV, and SCBV were detected in 121 out of 129 genotypes using the RT-PCR and PCR assays. Based on their response to the viruses, the tested genotypes were categorized into different resistance grades: highly resistant (grade 1), resistant (grade 2), moderately resistant (grade 3), susceptible (grade 4), and highly susceptible (grade 5). The results of the study provide valuable information about elite resistance resources that can be used for the prevention and control of mosaic disease. These resistant genotypes could also serve as potential donors for mosaic and leaf fleck disease resistance in breeding programs.

Differential Physiological Responses to Different Drought Durations among a Diverse Set of Sugarcane Genotypes

Drought severely limits sugarcane productivity in many regions of the world. This study characterized physiological responses to different drought durations in a diverse set of sugarcane genotypes in two crop cycles (plant and ratoon cane). A split-plot design was used where three drought treatments, namely, no drought (SD0), short-term drought (SD1), and long-term drought (SD2), were assigned to main plots and six diverse sugarcane genotypes to subplots. Drought reduced photosynthesis, leaf area index, and biomass yield. However, the study found significant differences in physiological responses to drought among genotypes in both crops. F03-362 (F1), KK09-0358 (BC1), and KK3 (cultivar) demonstrated greater tolerance to drought by maintaining comparatively higher photosynthetic activity, while KK09-0939 (BC2) and TPJ04-768 (BC1) were more sensitive. KK3 and UT12 (cultivar) consistently maintained comparatively higher levels of photosynthesis under drought in the ratoon crop, although stomatal conductance values were comparable to those of other genotypes. Drought significantly reduced dry matter in all genotypes, but more so in the two cultivars. The study demonstrated variable levels of sensitivity to drought among diverse genotypes with different physiological responses being induced by different drought treatments. This information is useful for sugarcane production management and breeding programs.

Rice Ratooning: A Pioneering Strategy for Enhancing Rice Productivity and Embracing Climate Change Adaptation and Mitigation

The global demand for rice as a primary staple food, especially in Asia, has intensified the need for increased rice production. However, traditional rice cultivation methods such as double-cropping have adverse environmental impacts and are affected by water scarcity due to changing climate conditions. In this context, the ratoon rice system, which involves regenerating a second rice crop from the same plant after the main harvest, offers a promising solution. Ratoon cropping reduces production costs, labor, and water usage while being more environmentally friendly. This review paper aims to explore the best management practices for enhancing ratoon rice system productivity and climate change adaptation. Various strategies are discussed such as optimal varietal selection, timing of sowing and harvesting, establishment techniques, cutting height of the main crop, water and nutrient management, weed control and the use of plant growth regulators. The results suggest that implementing these practices can lead to better ratoon crop yields and economic benefits. Furthermore, sustainability assessments have shown that ratoon rice cultivation can reduce greenhouse gas emissions, making it a more environmentally sustainable option compared to conventional rice cropping methods.

Sustained organic amendments utilization enhances ratoon crop growth and soil quality by enriching beneficial metabolites and suppressing pathogenic bacteria.

Organic soil amendments such as filter mud (FM) and biochar (BC) can potentially influence the abundance and composition of metabolites. However, our current understanding of the stimulatory effects of FM and BC's long-term impact on stress-regulating metabolites, such as abscisic acid (ABA), jasmonic acid (JA), melatonin, and phenyllactic acid (PLA), and these substrates regulatory effects on disease-causing bacteria in sugarcane ratooning field, which is susceptible to nutrients depletion, diseases, etc., remain poorly understood. Additionally, little is known about how the long-term interaction of these substrates and compounds influences sugarcane ratooning soil enzyme activities, nutrient cycling, and crop growth performance. To answer these questions, we adopted metabolomics tools combined with high-throughput sequencing to explore the stimulatory effects of the long-term addition of FM and BC on metabolites (e.g., PLA and abscisic aldehyde) and quantify these substrates' regulatory effects on disease-causing bacteria, soil enzyme activities, nutrient cycling, and crop growth performance. The result revealed that ratoon crop weight, stem diameter, sugar content, as well as soil physico-chemical properties, including soil nitrate (NH3 +-N), organic matter (OM), total nitrogen (TN), total carbon (TC), and β-glucosidase, marked a significant increase under the BC and FM-amended soils. Whereas soil available potassium (AK), NO3 -N, cellulase activity, and phosphatase peaked under the BC-amended soil, primarily due to the enduring effects of these substrates and metabolites. Furthermore, BC and FM-amended soils enriched specific stress-regulating metabolites, including JA, melatonin, abscisic aldehyde, etc. The sustained effects of both BC and FM-amended soils suppressed disease-causing bacteria, eventually promoting ratooning soil growth conditions. A number of key bioactive compounds had distinct associations with several beneficial bacteria and soil physico-chemical properties. This study proves that long-term BC and FM application is one of the eco-friendly strategies to promote ratoon crop growth and soil quality through the enrichment of stress-regulating metabolites and the suppression of disease-causing bacteria.

Evaluating Rice Varieties for Suitability in a Rice–Fish Co-Culture System Based on Lodging Resistance and Grain Yield

Rice–fish co-cultures have been practiced for over 2000 years, and they have tremendous potential in terms of increasing food security and economic benefits. However, little research has been conducted into achieving stable yields and high lodging resistance with regard to rice while simultaneously promoting the harmonious and healthy growth of fish in rice–fish co-culture paddy fields. We conducted a field study aimed at selecting suitable rice varieties for rice–fish co-culture systems (encompassing both ratoon and main crop). This selection process was grounded in an evaluation of lodging resistance and grain yield among 33 rice varieties used throughout the studied region. The results revealed a range of lodging indices of the main crop for the second internode, spanning from 62.43 to 138.75, and the annual grain yield (main crop and ratoon crop) ranged from 7.17 to 13.10 t ha−1 within rice–fish co-culture systems. We found that the use of rice–fish co-culture farming could improve the milling quality, nutrient quality, and appearance quality of rice, though the improvement gained through co-culturing varied across rice varieties. Moreover, the lodging index of the three basal internodes of rice plants was significantly and positively correlated with the plant height and the culm fresh weight, but it was negatively correlated with the bending strength of the rice basal internodes. Additionally, the 33 tested rice varieties were clustered in accordance with their lodging resistance (i.e., high resistance with lodging indices 62.43–75.42; medium resistance with lodging indices 80.57–104.62; and low resistance with lodging indices 113.02–138.75) according to the hierarchical cluster analysis. The 33 rice varieties were also clustered in accordance with the annual (main crop and ratoon crop) grain yield (i.e., high yield with 11.17–13.10 t ha−1; medium yield with 10.15–10.83 t ha−1; and low yield with 7.16–9.88 t ha−1). In all, 11 rice varieties were identified by a comprehensive evaluation as suitable varieties for grain production in the rice–fish co-culture system. These varieties displayed favorable traits, including a high annual rice yield, strong lodging resistance, and good grain quality. This is the first study to systematically evaluate rice varieties based on grain yield, lodging resistance, and grain quality in rice–fish co-culture systems.

Flower yield potential of Pyrethrum (<em>Chrysanthemum cinerariaefolium</em> L.) under various NPK Levels in the Lower Hills of Uttarakhand, India

Purpose: A favorable environment is available for the cultivation of Pyrethrum in the hilly regions of India, as well as in some mountainous areas of India. In view of the demand for Pyrethrin, it is very necessary to promote the huge cultivation of Pyrethrum. There is no misconception that research work has not been done to promote Pyrethrum, but the data related to the assessment of the right amount of nutrients required for the crop is not available in research related to agrotechnology. If the crop is to be taken as a ratoon crop, then it is very important to estimate the amount of nutrients for single recommendation of crop cultivation. Research Method: A research experiment was conducted in the year 2021 at the CSIR-Central Institute of Medicinal and Aromatic Plant Research, Centre Purara, Bageshwar (Uttarakhand) to study the flower yield potential of Pyrethrum under various NPK levels in the lower hills of Uttarakhand. The experiment was carried out in Complete Randomized Block Design. The six different levels of NPK (kg ha-1) were taken as treatments, i.e., control, 60:60:20, 80:70:30, 100:80:40, 120:90:50, and 150:100:60. Various plant growth and yield parameters considered in the study include plant height (cm), plant diameter (cm), number of flower heads, fresh flower weight plant-1 (g), dry flower weight plant-1(g), fresh flower yield (kg ha-1), dry flower yield (kg ha-1), Pyrethrin concentration (%) and yield (kg ha-1). Findings: Based on the research findings, it seems that the NPK level of 120:90:50 is the best combination to obtain the highest dry flower yield (310.49 kg ha-1) in the lower hills of Uttarakhand. However, the fresh flower weight obtained was the highest under the NPK level of 100:80:40 i.e., 840.47 kg ha-1, but it’s dry flower yield estimated was 301.93 kg ha-1 which was the second highest yield after 310.49 kg ha-1. This could be due to the difference in moisture levels in fresh flowers at the time of harvesting.Research Limitation: Considering the climate of the hilly regions of Uttarakhand, not much work has been done to assess and standardize the proper amount of nutrients required for Pyrethrum crop cultivation, which needs to be done.Originality/ Value: In the hilly areas of Uttarakhand, farmers are interested in the cultivation of Pyrethrum, but if farmers will adopt this crop cultivation as a ratoon crop, then in such a situation it is absolutely necessary to assess the proper amount of nutrients. This research will prove helpful in promoting the cultivation of Pyrethrum in the hilly areas of Uttarakhand.

Sugarcane stem borers, Sesamia spp. (Lepidoptera: Noctuidae) infestation in plant and ratoon crops

Sugarcane stem borers, Sesamia spp. (Lepidoptera: Noctuidae) infestation in plant and ratoon crops

Water-efficient genotypes along with conservation measures significantly reduce the green and blue water footprints in sugarcane (Saccharum spp.)

Sugarcane crop is irrigated using surface, overhead, and drip irrigation methods. Increased water use in sugarcane is a major concern around the world, implying the need for water accounting, developing water-efficient hybrids and water-saving agro-techniques for long-term conservation and use of water. “Water Footprint (WF)” is a measure of both direct and indirect water usage accountable for any product and/or process. In praxis, ‘Green Water Footprint’ (GWF) and ‘Blue Water Footprint’ (BWF) are extremely crucial for the restoration of essential ecosystem services (ES), such as sugarcane production. The WF metric was used as a priority tool in our study to evaluate water-efficient sugarcane hybrids, germplasm clones, deficit irrigation scheduling, crop geometry, and water conservation measures. Precise and accurate WF quantification would supplement the decision-making processes for managing available water resources in sugarcane agriculture. In split plot experimental design two research investigations on water management in sugarcane were undertaken at the ICAR-Sugarcane Breeding Institute, Coimbatore, Tamil Nadu, India. The major objective of the research trails was to find out suitable sugarcane hybrids and agronomic management practices to minimise water usage in sugarcane cultivation in water stressed and drought prone areas of tropical India. Our investigation comprised two phases; the first one being assessment of the impact of deficit irrigation scheduling, planting techniques and water conservation measures in sugarcane production, while the second phase dealt with genotypic evaluation under variable irrigation scheduling. Results showed that BWF reduced significantly in the first ratoon crop due to deficit irrigation scheduling coupled with planting of two budded setts and application of sugarcane trash at the rate of 5 t ha−1. Sugarcane hybrids viz., Co 85019, Co 10026, Co 12009, Co 13014, Co 14002, Co 14025, Co 15015, and Co 15018 were more water efficient, with a lower total WF. Among the germplasm clones, Fiji 55, ISH 111, ISH 107, Pathri, and Gungera exhibited lower GWF, BWF and total WF.