Total Dry Matter Accumulation Research Articles

Residual Effect of Water Soluble Fertilizers on Productivity and Nutrients Uptake of Cowpea in Aerobic Rice-cowpea Cropping Sequence under Fertigaton

A field experiment was under taken at University of Agricultural Sciences, GKVK, Bengaluru, Karnataka state, India to study the residual effect of fertigation of water soluble fertilizers on productivity and nutrients uptake of cowpea under aerobic rice-cowpea cropping sequence during Kharif 2015-16 and 2016-17 with 16 treatments replicated thrice in randomized block design. Significantly higher plant height (58.47 cm), number of branches plant-1 (11.71) and total dry matter accumulation plant-1 (70.60 g) were recorded in fertigation with 100% RDF through water soluble fertilizer at 8 DI. Likely, similar treatment 100% RDF through water soluble fertilizer at 8 DI was recorded significantly higher number of pods plant-1 (16.58), pod length (16.67 cm), seeds per pod (16.10), test weight (11.93 g), seed yield (12.94 q ha-1) and haulm yield (26.17 q ha-1). While higher total uptake of N, P and K by cowpea (68.94, 14.67 and 61.39 kg N, P and K ha-1, respectively) was recorded in 100% RDF through water soluble fertilizers at 4 DI (T5) than all other treatments. 100% RDF through WSF at 8 DI (T8) was recorded notably higher total Ca, Mg and S uptake by cowpea (50.71, 24.71 and 12.09 kg Ca, Mg and S ha-1, respectively). Significantly higher uptake of total Fe, Zn and Cu by cowpea crop (680.23, 91.30 and 38.27 g ha-1, respectively) was recorded with 100% RDF through water soluble fertilizers at 8 DI (T8). Total uptake of Mn was recorded higher by cowpea was observed (181.67 g ha-1) in 100% STCR dose through water soluble fertilizers at 4 DI (T11).

Growth and yield of direct seeded rice as influenced by irrigation levels and varieties

The combined influence of agronomic, environmental and genetic variables results in better crop yield. Among these components, an appropriate irrigation system and varietal choice are crucial. With this background, a field experiment with a split-plot layout was planned during the summer period of 2020 at the Agriculture and Horticultural Research Station, Bhavikere, Karnataka, India, to examine the effects of four different irrigation levels (0.75, 1.00, 1.25 and 1.50 IW/CPE ratio) in the main plot and four different varieties (Local variety, Jyothi, MAS 946-1 and MAS-26) in the subplots on growth and yield performance under direct seeded rice condition. Results of the experiment revealed that among four different levels of irrigation, scheduling irrigation at 1.50 IW/CPE ratio recorded higher growth and yield parameters at harvest viz., plant height (82.76 cm), number of tillers per plant (13.29), leaf area index (2.66), total dry matter accumulation (73.36 g/plant), number of panicle per plant (10.35), panicle length (21.59 cm), number of filled grains per panicle (90.4), grain yield (5569 kg/ha) and straw yield (7514 kg/ha). While, among the varieties used for the study, MAS 946-1 recorded the higher growth and yield parameters at harvest (64.19 cm, 13.96, 2.45, 73.34 g/plant, 10.96, 21.25 cm, 84.3, 5743 kg/ha and 7288 kg/ha, respectively). Hence, scheduling irrigation at 1.50 IW/CPE ratio and use of MAS 946-1 variety demonstrated superior performance, making it most appropriate for maximising higher production under direct seeded rice condition. Bangladesh J. Bot. 53(3): 527-533, 2024 (September)

Effect of Nano Urea on Growth, Yield and Nutrient uptake of Finger Millet (Eleusine coracana L.)

Aim: The foliar application of nano urea is aimed at reducing the soil application of conventional urea. Nano fertilizers enhance crop growth and yield while enhancing nutrient uptake and reducing costs. They provide precise nutrient management, match crop growth stages, and offer an increased surface area for metabolic reactions. This boosts photosynthesis, leading to higher dry matter production and crop yield. Foliar application of nano urea (liquid) at tillering and booting stages in finger millet fulfills the nitrogen requirement and reflects higher crop productivity. Higher productivity of crops in a sustainable manner could be achieved by applying an appropriate combination of conventional fertilizers and nano fertilizers. Study Design: The experiment was laid out in split design with three replications. Place and Duration of Study: A field experiment was conducted in deep black soils at Agricultural Research Station, Siruguppa, during kharif 2022. Methodology: There were sixteen treatment combinations, consisting of different doses of nitrogen (no nitrogen, 50% RDN, 75% RDN and 100% RDN) with different concentrations of nano urea and conventional urea sprayed at tillering and booting stages for HR-13 variety of finger millet. Results: Application of 100% RDN has recorded significantly higher plant height, tillers plant-1, total dry matter accumulation, grain yield and straw yield (129.82 cm, 10.10, 36.17 g plant-1, 36.87 q ha-1 and 71.72 q ha-1, respectively) in comparison to no nitrogen and 50% RDN. However, 75% RDN (123.04 cm, 9.61, 34.02 g plant-1, 34.84 q ha-1 and 68.01 q ha-1, respectively) found on par with 100% RDN. Among foliar nitrogen, spray of nano urea @ 4 ml L-1 recorded significantly higher plant height (121.59 cm), tillers plant-1 (9.37), total dry matter accumulation (33.16 g plant-1), grain yield (31.97 q ha-1) and straw yield (65.52 q ha-1) compared to 0.5% and 1% conventional urea. However, nano urea @ 2 ml L-1 was on par with 4 ml L-1 nano urea and 1% conventional urea. Similar trend was recorded with regard to nutrient uptake by finger millet. Conclusion: Foliar application of nano urea reduced the dosage of conventional urea by 25 per cent.

Influence of arbuscular mycorrhizal species on total dry matter accumulation, yield and its attributes of groundnut under water stress

Influence of arbuscular mycorrhizal species on total dry matter accumulation, yield and its attributes of groundnut under water stress

Effect of Heat Stress during Reproductive Stage on Plant Growth, Total Biomass Production and their Correlation with Grain Yield in Rice

Rice (Oryza sativa L.) is highly sensitive to high temperature during its reproductive stages. This study aims to elucidate the effects of heat stress during reproductive stage on plant growth, total dry matter accumulation, and their correlation with grain yield in diverse rice genotypes. A field experiment in split plot design was conducted at G.B.P.U.A.& T., Pantnagar during rainy season 2022-23, where high temperature stress was imposed on 15 rice genotypes during reproductive stage (after panicle initiation till maturity) using a polytunnel. The results showed that heat stress lead to reduction in dry matter accumulation and harvest index in 10 genotypes, although with different magnitude. The genotypes were screened into tolerant and susceptible based on yield reduction by comparing with the genotype N-22, which was used as a check for heat stress. It was observed that the genotypes, IET 29415, MTU-1282, MTU-1121, NLR-40042 and US-314 maintaining higher biomass and HI under heat stress conditions were able to maintain grain yield. The identified genotypes with better performance under heat stress conditions offer valuable genetic resources for breeding programs aimed at improving heat tolerance in rice.

Comparação das distribuições Normal, Logística, Laplace e t de Student para o erro experimental na descrição bayesiana do acúmulo de matéria seca de Allium sativum

ABSTRACT: This study assessed distributions associated with Bayesian nonlinear modeling error in the description of total plant dry matteraccumulation (TDMA) of Allium sativumas a function of days after planting (DAP). According to the DIC criterion, Logistic and Gompertzmodels that use student’s t distribution error exhibited the highest DIC with logistic error distribution. In general, the difference of DIC in all the scenarios was not more than 5.The Bayes factor (BF) criterion showed no difference in the Logistic and Gompertzmodel fit when four distributions are used for the errors, where BF values do not exceed 2. Posterior distributions and the usual estimators of Logistic and Gompertz model parameters were similar even forvaried error distribution. In summary, there was no difference in the use of 4 distributions associated with the modeling error of garlic plant growth by the Bayes factor, whereby the results showed that alternating between error distributions significantly changes the number of Markov Chain Monte Carlo (MCMC) iterations.

Effect of automated sensor-driven irrigation and fertigation on green pepper (Capsicum annuum L.) growth, phenology, quality and production

This research aimed to optimize green pepper cultivation with automated sensor-based irrigation and fertigation, supplemented by roof water harvesting under protected cultivation. The findings demonstrated that employing a sensor-based irrigation regimen at 75 % available soil moisture (ASM) coupled with 125 % of the recommended dose of fertilizer (RDF) significantly improved both the growth and yield characteristics of pepper. This combination notably improved yield attributing parameters as well as total fruit yield (60,089 kg ha−1). Also, the resource use efficiency metrics viz., water use efficiency (16.75 kg m−3), energy productivity (0.80 kg MJ−1), nutrient use efficiency (79.5 kg kg−1) and benefit-cost ratio of 2.07, indicated superiority. Correlation between yield and variables viz., individual fruit weight (r = 0.98), number of fruits per plant (r = 0.96), total dry matter accumulation (r = 0.96), and fruit volume (r = 0.94) found positive at 1 % probability, displaying the strongest associations. Growth variables such as dry matter of leaves (R2=0.927), individual fruit weight (R2=0.922), and fruit volume (R2=0.847) at P ≤ 0.0001 contributed significantly to the yield. Remarkably, during the year 2020, the system collected 774 m3 of water, satisfying 100 % of the green pepper's water requirement for two seasons.

Intelligent fertigation improves tomato yield and quality and water and nutrient use efficiency in solar greenhouse production

Intelligent fertigation is a sustainable solution for optimising water and fertiliser input, thus minimising environmental pollution in vegetable cultivation facilities and reducing labour costs in agricultural practices. It is important to optimise irrigation scheduling parameters to specific crops to ensure water and nutrient use efficiency. A field experiment was conducted in Shouguang, Shandong Province, to investigate the effects of irrigation scheduling with different treatments (farmer drip irrigation FI, intelligent irrigation II1, and intelligent irrigation II2) on tomato growth, irrigation water and nutrient use efficiency over two growth seasons. Intelligent irrigation II1 and II2 utilised FDR sensors to control the moisture range within 80–95% and 80–85% field capacity (FC) for automatic irrigation scheduling, respectively. Intelligent irrigation (II1 and II2 treatments) reduced irrigation rate by 24.3–63.8% in comparison with FI treatment, significantly increasing total dry matter accumulation, nutrient uptake, yield and fruit quality of tomato. II2 treatment further reduced the irrigation rate by 31.6–32.3% compared to II1 treatment, with no significant difference in tomato yield and quality. Root dry matter, root-shoot ratio, 0–2 mm diameter root length and root surface area, 0–1.5 mm diameter root tips, and >3.5 mm diameter root volume were significantly increased under intelligent irrigation treatments. Positive correlations between irrigation water productivity; nitrogen, phosphorus, and potassium use efficiency; and the indices of length, surface area, tips, and volume of roots were highly significant. Intelligent fertigation system (IFS) maintained soil moisture within a suitable range through high-frequency irrigation scheduling, promoted the growth of 0–2 mm diameter roots, which were responsible for absorbing, acquiring, and transporting water and nutrients in the soil, and reduced water loss and nutrient leakage. Taken together, the intelligent fertigation system presented herein is an effective fertigation strategy to improve irrigation water and nutrient use efficiency.

Compatibility of wild rootstocks in the production of cherry tomato seedlings

Growing tomato crops is a highly significant activity in Brazil; however, several factors limit tomato productivity, mainly soil-borne diseases which, without proper control, can compromise the entire crop production. The proper use of grafting techniques emerges as an alternative to overcome barriers that limit tomato production in regions with unfavorable growth conditions. The use of rootstocks resistant to root diseases is seen as a viable option for tomato production. In this context, the objective of this work was to evaluate the compatibility and efficiency of rootstocks for cherry tomatoes. A randomized block design was used, with five treatments and four replications; each plot consisted of 36 grafted seedlings. The treatments consisted of rootstocks of Eggplant, Jurubeba, Jilo, and Tomato (Intacto; Feltrin Sementes®), and a Control (cherry tomato without grafting). All rootstocks were compatible with cherry tomatoes. Moreover, seedlings grafted onto Jurubeba rootstocks presented results closest to the Control (cherry tomatoes). Seedlings grafted onto Jurubeba and Eggplant rootstocks presented the best results regarding vegetative development and total dry matter accumulation. Jurubeba and Eggplant rootstocks are viable alternatives for grafting cherry tomato seedlings. All utilized rootstocks can be further investigated for their resistance to root diseases affecting tomato crops.

Magnesium fertilizer application increases peanut growth and pod yield under reduced nitrogen application in southern China

This study investigated the effect of magnesium application on peanut growth and yield under two nitrogen (N) application rates in acidic soil in southern China. The chlorophyll content, net photosynthetic rate and dry matter accumulation of the N-sensitive cultivar decreased under reduced N treatments, whereas no effect was observed on the relevant indicators in the N-insensitive variety GH1026. Mg application increased the net photosynthetic rate by increasing the expression of genes involved in chlorophyll synthesis and Rubisco activity in the leaves during the pegging stage under 50%N treatment, while no effect on the net photosynthetic rate was observed under the 100%N treatment. The rate of dry matter accumulation at the early growth stage, total dry matter accumulation and pod yield at harvest increased after Mg application under 50%N treatment by increasing the transportation of assimilates from stems and leaves to pods in both peanut varieties, whereas no effect was found under 100%N treatment. Moreover, Mg application increased the NUE under 50%N treatment. No improvement of NUE in either peanut variety was found under 100%N treatment, while Mg application under the 50%N treatment can obtain a higher economic benefit than the 100%N treatment. In acidic soil, application of 307.5 kg ha−1 of Mg sulfate fertilizer under 50% reduced nitrogen application is a suitable fertilizer management measure for improving carbon assimilation, NUE and achieve high peanut yields in southern China.

Effect of Foliar Nutrition on Growth and Yield of Pigeonpea [Cajanus cajan. (L.) Mill sp.

Pigeonpea is most important rainfed pulse crop of Karnataka. Yield of pigeonpea is fluctuating due to variation in climate causing flower drop and poor pod set. The field experiment was conducted to study growth and yield of pigeonpea as influenced by foliar nutrition. The experiment consisted of foliar application of two types of nutrients (19:19:19 and Pulse magic), two growth promoters (NAA, and N - Triacontanol) and their combinations at flowering and pod formation stages. The growth and yield attributes varied significantly and RDF + foliar application of 1% pulse magic at flowering and pod formation stage recorded significantly higher plant height (144.6 cm), number of branches (16.8 plant‑1), leaf area (3218 cm2 plant-1), total dry matter accumulation (135.5 g plant-1), absolute growth rate (0.812 g plant-1 day-1,), crop growth rate (5.19 g m-2 day-1) and relative growth rate (0.01 g g-1 day-1) as compared to control (122.2 cm, 12.9, 2421 cm2 plant-1, 89.4 g plant-1, 0.633 g plant-1 day-1, 4.24 g m-2 day-1 and 0.007 g g-1 day-1, respectively) at harvest. Higher seed yield (1590 kg ha-1), stalk yield (4308 kg ha-1) and harvest index (0.26) recorded with the application of RDF + foliar application of 1% pulse magic at flowering and pod formation stage and lower seed yield, stalk yield and harvest index (1104 kg ha-1, 3416 kg ha-1 and 0.23, respectively) was recorded with control treatment.

Effect of Lime Application for Neutralizing Fertilizer Acidity on Growth and Yield of Maize in Alfisols

A field experiment was conducted at College of Agriculture, V. C. Farm, Mandya during Kharif 2021-22 to evaluate the effect of lime application for neutralizing fertilizer acidity on growth and yield of maize in Alfisols. There were eight treatments that include 500 kg lime (T3) and 250 kg granular dolomite (T4) + FYM and recommended dose of fertilizers (RDF), 100% RDF and FYM + 100 and 50% fertilizer acidity neutralization with lime (T5 and T6) and granular dolomite (T7 and T8), absolute control (T1) and FYM + 100 % RDF (T2). The experiment was laid out in Randomized Complete Block Design with three replications. The results revealed that application of lime @ equivalent to 100% neutralization of fertilizer acidity with 100% RDF and FYM (T5) recorded significantly higher plant height (221.56 cm), number of leaves (13.01 plant-1), leaf area (6389 cm2 plant-1) and total dry matter accumulation plant-1 (168.74 g plant-1) which was on par with T8, T6, T7 and T4. Similarly, significantly higher yield parameters like cob length (21.98 cm), cob girth (20.01 cm), number of rows cob-1 (16.86), number of kernels row-1 (36.98) and test weight (35.98 g) were recorded in T5 when compared to T2, T3 and T1. Kernel and stover yield (81.57 and 90.67 q ha-1, respectively) was observed to be significantly higher in T5 treatment which was on par with T6 which clearly indicated that 100% neutralization of fertilizer acidity with lime along with 100% recommended dose of fertilizer and FYM is necessary for obtaining higher growth and yield of maize.

Post-anthesis dry matter and nitrogen accumulation, partitioning, and translocation in maize under different nitrate-ammonium ratios in Northwestern China.

An appropriate supply of ammonium (NH4+) in addition to nitrate (NO3-) can greatly improve plant growth and promote maize productivity. However, knowledge gaps exist regarding the mechanisms by which different nitrogen (N) fertilizer sources affect the enzymatic activity of nitrogen metabolism and non-structural carbohydrates during the post-anthesis period. A field experiment across 3-year was carried out to explore the effects of four nitrateammonium ratio (NO3-/NH4+ = 1:0 (N1), 1:1 (N2), 1:3 (N3), and 3:1 (N4)) on postanthesis dry matter (DM) and N accumulation, partitioning, transportation, and grain yield in maize. NO3-/NH4+ ratio with 3:1 improved the enzymatic activity of N metabolism and non-structural carbohydrate accumulation, which strongly promoted the transfer of DM and N in vegetative organs to reproductive organs and improved the pre-anthesis DM and nitrogen translocation efficiency. The enzymatic activities of nitrate reductase, nitrite reductase, glutamine synthetase, glutamine oxoglutarate aminotransferase, and non-structural carbohydrate accumulation under N4 treatment were increased by 9.30%-32.82%, 13.19%-37.94%, 4.11%-16.00%, 11.19%-30.82%, and 14.89%-31.71% compared with the other treatments. Mixed NO3--N and NH4+-N increased the total DM accumulation at the anthesis and maturity stages, simultaneously decreasing the DM partitioning of stem, increasing total DM, DM translocation efficiency (DMtE), and contribution of pre-anthesis assimilates to the grain (CAPG) in 2015 and 2017, promoting the transfer of DM from stem to grain. Furthermore, the grain yield increased by 3.31%-9.94% (2015), 68.6%-26.30% (2016), and 8.292%-36.08% (2017) under the N4 treatment compared to the N1, N2, and N3 treatments. The study showed that a NO3-/NH4+ ratio of 3:1 is recommended for high-yield and sustainable maize management strategies in Northwestern China.

Optimizing rice yield, quality and nutrient use efficiency through combined application of nitrogen and potassium.

Reasonable nitrogen (N) and potassium (K) application rates can effectively improve fertilizer use efficiency, rice yield and quality. A two-year field experiment was conducted with combined application of three N rates (135, 180, and 225 kg ha-1, denoted as N1-N3) and four K rates (0, 90, 135, and 180 kg ha-1, denoted as K0-K3) using super indica hybrid rice cultivar Yixiangyou (YXY) 2115 to explore the effects of co-application of N and K on rice growth and development. The results indicated that the combined application of N and K had significantly interactive effects on dry matter (DM) accumulation, nutrients absorption, N harvest index (NHI), K harvest index (KHI), spikelets per panicle and most rice quality indexes. The highest total DM accumulation (17998.17-19432.47 kg ha-1) at maturity stage was obtained under N3K2. The effect of co-application of N and K on nutrients absorption and utilization varied between the two years and within each year. The highest total N and K accumulations at maturity stage were observed under N3K1 and N3K2, respectively, while the highest N recovery efficiency (NRE) and K recovery efficiency (KRE) were observed under N1K3. High expression levels of N and K metabolism-related genes in rice grains were observed under N3K2 or N3K3, consistent with N and K uptake. Co-application of N and K increased rice yield significantly and the highest yield (6745.02-7010.27 kg ha-1) was obtained under N2K2. As more N was gradually applied, rice appearance quality improved but milling, cooking and eating quality decreased. Although appropriate application of K could improve rice milling, cooking and eating quality, it reduced appearance quality. The optimal milling, cooking and eating quality were obtained under N1K2, while the best appearance quality was obtained under N3K0. Overall, a combination of 135-210 kg ha-1 N and 115-137 kg ha-1 K application rates was recommended for achieving relatively higher yield and better quality in rice production.

The complex stress of waterlogging and high temperature accelerated maize leaf senescence and decreased photosynthetic performance at different growth stages

AbstractThe greenhouse effect caused by global warming was becoming more and more obvious, resulting in increased frequency of high temperature and high humidity, which significantly affected maize productivity. However, it was poorly understood how the interactions of high temperature and high humidity affected leaf senescence, photosynthetic performance and yield of summer maize. Three stress treatments including (a) high temperature stress (T), (b) waterlogging stress (W) and (c) complex stress (T‐W) were set at the third leaf stage (V3), the sixth leaf stage (V6) and the tasselling stage (VT) in 2019–2020 to explore the influence mechanism of complex stress. Each stress treatment period lasted 6 days. Non‐stressed plants served as control. Yield, antioxidant enzyme activity, photosynthetic characteristics, and dry matter accumulation were determined. Our study found that the activity of antioxidant enzymes was significantly decreased, while malonyldialdehyde (MDA) accumulation was increased under each stress treatment. As a result, the photosynthetic characteristics were impaired, manifested in a significant decrease in net photosynthetic rate (Pn), enzyme activities of phosphoenolpyruvate carboxylase (PEPCase) and ribulose diphosphate carboxylase (RUBPCase). The decrease in photosynthetic intensity affected by each stress treatment led to a significant decrease in total dry matter accumulation and grain yield. The most significant effects of waterlogging and combined stresses on yield occurred at the V3 stage, followed by the V6 and VT stages. However, the most significant effects of high temperature occurred at the VT stage, followed by the V6 and V3 stages. Moreover, the compound stress exacerbated damage to leaf senescence and photosynthetic properties of summer maize compared to the single stress of high temperature or waterlogging.

Effect of Sowing Environment and Varieties on Growth Attributes of Rain-fed Wheat under Sub-tropical Foothills of Jammu

A field experiment was conducted at the Research Farm Advanced Centre for Rain-fed Agriculture (ACRA), Rakh-Dhiansar of Sher-e-Kashmir University of Agricultural Sciences and Technology of Jammu. The experiment was laid out in factorial randomized block design with three replications at during Rabi season of 2018-19 to study the effect of six dates of sowing (31st October, 15th November, 30th November, 15th December, 30th December and 14th January) on growth attributes of two wheat varieties (PBW-175 and JAUW-598). The sowing of rain-fed was done at spacing of 20 cm in sandy loam soil. The observations were recorded on plant height, total dry matter accumulation, crop growth rate and relative crop growth rate of wheat crop. Growth of wheat in terms of plant height, dry matter accumulation, crop growth rate and relative growth rate at periodic intervals revealed that at all the growth stages, the growth characters of wheat showed a pronounced improvement with varieties and sowing environments. The data showed significant effects of different sowing time on plant height, total dry matter and crop growth rate while relative crop growth rate found to be non-significant. Among varieties total dry matter found to be significant at 90, 120 DAS and at harvest as well as CGR at 60-90 DAS and 90-120 DAS while plant height and RGR showed to be non-significant at periodic intervals. In addition, the interaction effects were significant in some of observations.

Results of Weed Density, Yield Attributes, and Yield on Wheat Crop were Influenced by Varying Broad-spectrum Herbicide Treatments in Eastern U.P., India

In the year 2015-16, a field experimental trial was conducted during the rabi season to assess the impact of various broad spectrum herbicide treatments on weed density and yield in wheat crops. The experiment followed a randomized block design with four replications, and a total of eight treatments were tested. The wheat cultivar DBW-17 was used as the test crop. Results showed that weed density and dry matter accumulation of weeds increased up to 90 days of crop growth, but decreased at 120 days in the weedy check treatment. In contrast, no weeds were recorded in the weed-free plot throughout the crop period. In terms of the wheat crop, the weed-free plot had the highest total dry matter accumulation at all stages (30 DAS-32.62, 60 DAS-278.26, 90 DAS-934.49 and 120 DAS-1276.28 g/m2), number of spikes (303.00/m2), number of grains/spike (51.00), test weight (40.40 g), length of spike (11.12 cm) and grain yield (5.422 t/ha). On the other hand, the weedy check treatment had the lowest total dry matter accumulation at all stages (30 DAS-28.78, 60 DAS-207.24, 90 DAS-679.82 and 120 DAS-932.76 g/m2), number of spikes (208.00/m2), number of grains/spike (42.00), test weight (36.41 g), length of spike (10.31 cm) and grain yield (2.641 t/ha).

Natural variation of an autophagy-family gene among rice subspecies affects grain size and weight

Elucidating the genetic basis of natural variation in grain size and weight among rice varieties can help breeders develop high-yielding varieties. We identified a novel gene, GW3a (Grain Weight 3a) (LOC_Os03g27350), that affects rice grain size and weight. gw3a mutants showed higher total starch content and dry matter accumulation than the wild type (WT), Nipponbare, suggesting that GW3a negatively regulates grain size and weight. Moreover, our study found that GW3a interacted with OsATG8 by cleaving it, suggesting that GW3a may be involved in the assembly of autophagosomes and starch degradation in plants. The haplotype analysis of GW3a showed functional differences between indica and japonica rice. Taken together, we conclude that GW3a is expressed in the autophagosome pathway regulating starch metabolism in rice, affecting yield-related traits, such as grain size, grain weight and thousand grain weight (TGW). Our findings also shed new light on autophagy-mediated yield trait regulation, proposing a possible strategy for the genetic improvement of high-yield germplasm in rice.

Studies on Influence of Lipo-chito Oligosaccharides, Nano and Water-Soluble Fertilizer on Growth and Growth Parameters of Soybean [Glycine max (L.) Merrill

A field experiment was conducted at University of Agricultural Sciences, GKVK, Bengaluru during kharif 2022 to studies on influence of lipo-chito oligosaccharides, nano and water-soluble fertilizer on growth and growth parameters of soybean [Glycine max (L.) Merrill]. The experiment was laid out in randomized complete block design with ten treatments and replicated thrice. The results revealed that application of 75% recommended dose of NP + 100 % K along with soil application of lipo-chito oligosaccharide (LCO) fortified bio-fertilizer @ 10 kg ha-1 + foliar application of 19:19:19 @ 2 % spray at flowering and pod filling stages recorded significantly higher leaf area, leaf area index at 60 DAS (1772 cm2 plant-1 and 4.91 respectively), leaf area duration (57.59 and 81.07 cm2 day-1 at 30-60 DAS and 60 DAS-harvest, respectively), no. of nodules plant at 35 DAS (31.12), total dry matter accumulation (12.74 and 20.05 g plant-1 at 60 DAS and harvest, respectively), absolute growth rate (0.24 and 0.30 g day-1 at 30-60 DAS and 60 DAS-harvest, respectively), crop growth rate (8.15 and 9.21 g cm-2 day-1 at 30-60 DAS and 60 DAS-harvest, respectively) and relative growth rate (0.031 and 0.040 g g day-1 at 30-60 DAS and 60 DAS­­-at harvest, respectively).

Effect of Crop Specific Blended Fertilizers on Growth and Yield of Maize (Zea mays L.)

A Field experiment was conducted during Rabi 2022-23 at Agricultural and Horticultural Research Station, Kathalagere, KSNUAHS, Shivamogga, to study the effect of crop specific blended fertilizers on the growth and yield of maize. The experiment was laid out in Randomized Complete Block Design with ten treatments replicated thrice. Nutrient composition of blended fertilizer used for basal application was 16:18:11:4:1 N:P2O5:K2O:S:Zn and for top dress was 27: 0:13 N:P2O5:K2O. The treatments T1, T2, T3 consisted of application of basal blended fertilizer @ 312.5, 412.5 and 515 kg ha-1, respectively and top dress blended fertilizer @ 237.5, 312.5 and 390 kg ha-1, respectively. Basal blended fertilizer @ 412.5 kg ha-1 + top dress of urea at 30 and 45 DAS (T4), Package of practice (PoP) through straight fertilizer (T5), PoP through complex fertilizer (T6), recommended dose through Urea, DAP, MOP and ZnSO4 + top dress of nano urea @ 0.4% at 30 and 45 DAS (T7), physical blending of Urea, SSP, MOP and ZnSO4 (16:18:11:4:1 N:P:K:S:Zn) for basal and Urea and MOP (27:0:13 N:P:K) for top dress (T8), farmers' practice (T9) and absolute control (T10). Among all treatments, the application of basal blended fertilizer @ 515 kg ha-1 + Top dress of blended fertilizer @ 390 kg ha-1 recorded the maximum plant height (222.4 cm), number of leaves (10.3 plant-1), total dry matter accumulation (285.86 g plant-1), cob length (21.31 cm), cob girth (18.31 cm), number of kernels per cob (516.57) and test weight (24.22 g) at harvest as compared to PoP through straight and complex fertilizer and absolute control. The same treatment recorded significantly higher kernel and straw yield (69.51 and 89.36 q ha-1, respectively) in comparison to other treatments but it was on par with T2, T5 and T6. The treatment T3 recorded 27.8 % higher yield compared to T9. In study area the application of basal blended fertilizer @ 515 kg ha-1 + Top dress of blended fertilizer @ 390 kg ha-1 is recommended to achieve higher growth and yield of maize.