Cob Weight Research Articles

Precision drip Irrigation System and Foliar Application of Biostimulant and Fertilizers Containing Micronutrients Optimize Photochemical Efficiency and Grain Yield of Maize (Zea mays L)

Abstract Asymmetric drought propagation and depletion of soil nutrients threaten cereal crop productivity worldwide, calling for the application of validated agronomic practices to curtail their effect on crop production. This study evaluated the effect of precision drip irrigation, biostimulant, and micronutrients application on photochemical efficiency and yield of maize.An experiment laid in a randomized complete block design with irrigation and water stress was established in 2022 and 2023 growing seasons at the experimental area of the University of Debrecen. Other treatments included T1 (non-microbial biostimulant from plant origin), T2 (zinc based chemical fertilizer), T3 (boron and molybdenum based chemical fertilizer), and T4 (control). Data was collected on steady-state fluorescence (F’), maximal fluorescence (Fm’), quantum photosynthetic yield or efficiency of photosystem II (ΦPSII or Y(II)), electron transport rate (ETR), and grain yield and yield components. Precision drip irrigation significantly optimized ΦPSII, ETR, cob weight, number of seeds per cob, weight of 1000 seeds and grain yield. The biostimulant and micronutrients optimized Fm’, ΦPSII, and ETR at VT and R2 growth stages. Regardless of the water management regime, T1, T2 and T3 seasonally optimized grain yield. Between water management regimes, biostimulant had the highest yield optimization effect under precision drip irrigation in the season with elevated water stress.Optimum photochemical efficiency and grain yield is achievable through precision drip irrigation, biostimulant, and micronutrient application. However, further research involving 2–3 application times at critical stages of maize under precision drip irrigation and/or combined application of these treatments at season specific precision drip irrigation is required.

Inoculation with Azospirillum brasilense as a Strategy to Reduce Nitrogen Fertilization in Cultivating Purple Maize (Zea mays L.) in the Inter-Andean Valleys of Peru.

Purple maize has gained global significance due to its numerous nutraceutical benefits. However, sustaining its production typically requires high doses of nitrogen fertilizers, which, when applied in excess, can contaminate vital resources such as soil and water. Inoculation with nitrogen-fixing microorganisms, such as those from the Azospirillum genus, has emerged as an alternative to partially or fully replace nitrogen fertilizers. This study aimed to evaluate the inoculation effect with A. brasilense and varying nitrogen fertilization levels on the yield and quality of purple maize. The experiment was carried out using a randomized complete block design (RCBD) with a 2 × 5 factorial arrangement and five replications. Treatments comprised two inoculation levels (control without inoculation and inoculation with A. brasilense) under five nitrogen doses (0, 30, 60, 90, and 120 kg∙ha-1, applied as urea). Inoculation with A. brasilense resulted in a 10.5% increase in plant height, a 16.7% increase in root length, a 21.3% increase in aboveground fresh biomass, a 30.1% increase in root fresh biomass, and a 27.7% increase in leaf nitrogen concentration compared to the non-inoculated control. Regarding yield, the inoculated plants surpassed the control in both purple maize yield (kg∙ha-1) and cob weight by 21.8% and 11.6%, respectively. Across all fertilization levels and parameters assessed, the inoculated treatments outperformed the control. Furthermore, for parameters, namely plant height, leaf nitrogen content, and cob dimensions (length, diameter, and weight), the A. brasilense inoculation treatment with 90 kg N∙ha-1 was statistically equivalent or superior to the non-inoculated control with 120 kg N∙ha-1. These results indicate that inoculation with A. brasilense positively impacted purple maize at all nitrogen levels tested and improved nitrogen use efficiency, enabling a reduction of 30 kg N∙ha-1 without compromising performance in key parameters.

Effects of Vermicompost and Blended NPSB Fertilizer on Major Physicochemical Properties of Soil and Economy of Maize Production at Bako, Central Ethiopia

Integrated vermicompost and blended NPSB inorganic fertilizer are needed to improve the soil's fertility status, which can raise output and revenue. Thus, the purpose of the experiment was to ascertain how major physicochemical properties of the soil at Bako were affected by the application of blended NPSB fertilizer and vermicompost. Factorial combinations of four levels of vermicompost (0, 2, 4 and 6 tons ha<sup>-1</sup>) and four levels of NPSB blended inorganic fertilizer (0, 50, 100 and 150 kg ha<sup>-1</sup>) were laid out in Randomized Complete Block Design (RCBD) with three replications. The interaction of vermicompost and NPSB blended inorganic fertilizer had significant effects on ear diameter, grain yields, and harvest index and cob weight. The maximum grain yield (7503.7 kg ha<sup>-1</sup>) was obtained from application of blended NPSB fertilizer at the rate of 100 kg NPSB ha<sup>-1</sup> and 4 tons ha<sup>-1</sup> vermicompost rate with a net profit of 104850 birr and 6143% MRR with values to cost ratio of 3.47 birr profit per unit investment for midland maize production at Bako. Therefore, it can be said that the application of 100 kg NPSB ha<sup>-1</sup> and 4 t vermicompost ha<sup>-1</sup> was shown to be superior in terms of both grain yield and economic advantage, and it is therefore tentatively advised for use. To come to a definitive decision, the experiment needs to be repeated across a number of years, as this study was only conducted during one season at one site.

Growth, Phenology and Yield Attributes of A White Maize Genotype Sauwmopmdt273 Under Different Planting Configurations

A field experiment was carried out at the agronomy field of Sher-e-Bangla Agricultural University, during the period from July to October, 2018 with fifteen planting configurations viz., T1 (40 cm × 15 cm), T2 (40 cm × 20 cm), T3 (40 cm × 25 cm), T4 (45 cm × 15 cm), T5 (45 cm × 20 cm), T6 (45 cm × 25 cm), T7 (50 cm × 15 cm), T8 (50 cm × 20 cm), T9 (50 cm × 25 cm), T10 (55 cm × 15 cm), T11 (55 cm × 20 cm), T12 (55 cm × 25 cm), T13 (60 cm × 15 cm), T14 (60 cm × 20 cm), and T15 (60 cm × 25 cm) to study the growth, phenology, yield attributes and yield of a white maize genotype SAUWMOPMDT273. The experiment was laid out in a randomized complete block design with three replications. Regarding growth and yield parameters, the treatment 60 cm × 25 cm showed significantly the maximum plant height, tassel length and leaf area at silking, grain filling and at harvest. The highest area of an individual leaf 477.9, 879.3, and 496.3 cm2 as well as stem dry matter weight of 28.73, 21.35, and 27.40 g plant-1 respectively, below cob-node, at cob-node and above the cob-node during silking obtained from treatment 60 cm × 25 cm. The treatment 55 cm × 25 cm showed maximum biological yield (14.64 t ha−1) and 60 cm × 20 cm showed significantly the highest cob length (15.94 cm) and number of grains row−1 (20.00), but the highest number of grains cob−1 (231.50), 100 seed weight (29.99 g), grain weight cob−1 (59.81 g) were recorded from 55 cm × 25 cm. Sparser configuration (60×20 cm) requiring less seed rate, this configuration may be followed. Bangladesh Agron. J. 2024, 26(2): 67-76

Effects of liquid urea rates on nitrogen dynamics, growth, and yield of corn (Zea mays L.)

Arbitrary use of urea fertilizer reduces nitrogen use efficiency (NUE) and increases the risk of environmental pollution. An experiment was conducted at the Universiti Putra Malaysia from November 2019 to March 2020 to evaluate the application methods and rates of liquid urea (LU) on the yield performance of corn. The treatments were, U0 = control, GU100 = Granular urea (GU) 100%, LU100 = LU 100%, LU50 = LU 50% and LU33 = LU 33%, in two equal splits at 10th and 28th days after sowing (DAS) in randomized completely block design, replicates four. Results showed that plant height (206.99 cm, 216.92 cm, 214.61 cm), ear height (88.13 cm, 88.63 cm, 86.00 cm), days of maturity (88.75, 89.00, 86.75 days), number of grains per kernel row (32.25, 34.50, 33.75), fresh cob weight (10,886.60 kg ha−1, 10,946.60 kg ha−1, 10,927.93 kg ha−1) and 100-grain weight (20.51 g, 22.50 g, 21.39 g) of corn were not different significantly (p ≤ 0.05) in GU100, LU100 and LU50 treatments, respectively. The highest yield of corn was found with LU100 (6249.03 kg ha−1) treatment whereas the yield in LU50 (5666.50 kg ha−1) and GU100 (5746.64 kg ha−1) were not different significantly. Nitrogen (%) in plants was the highest in LU100 followed by LU50 treatment which was significantly higher than GU100 treatment. The total N content was also the highest in LU100 (102.83 kg ha−1) though the total N content was not different significantly in LU50 (77.62 kg ha−1) and GU100 (83.84 kg ha−1) treatments. The NUE was the highest in LU50 (66.92%) treatment followed by LU100 (51.47%) treatment. The results of the study suggested that LU was superior to GU and the LU100 was the best application rate while LU50 treatment was comparable to GU100 in corn cultivation.

Mulching tree leaves improve the growth, yield, and yield components of hybrid maize

The experiment was carried out at the Agroforestry Farm, Department of Agroforestry, Bangladesh Agricultural University, Mymensingh from November 2019 to March 2020 to assess the impact of tree leaf mulching on the growth, yield attributes, and yield of maize. The study used a Randomized Complete Block Design with three replications and six treatments. These treatments were: T0=Control (no mulch), T1=Akashmoni (Acacia auriculiformis) tree leaf mulch, T2=Segun (Tectona grandis) tree leaf mulch, T3=Kalo koroi (Albizia lebbeck) tree leaf mulch, T4=Jhau (Casuarina equisetifolia) tree leaf mulch, and T5=Jackfruit (Artocarpus heterophyllus) tree leaf mulch. The results showed that the Kalo koroi tree leaf mulch (T3) led to the highest values for various parameters such as plant height, number of effective tillers per plant, number of leaves per plant, leaf length, leaf diameter, number of cobs per plant, length, and diameter of cob, the weight of single cob, number of grains per cob, grain weight per cob, 100-grain weight, and grain yield of maize (221.18 cm, 0.93, 17.29, 79.26 cm, 7.30 cm, 4.18, 1.70, 21.11 cm, 6.08 cm, 212.12 g, 453.85 g, 138.91 g, 30.60 g, and 11.81 t/ha). Conversely, the lowest values were obtained in the control (T0) (no mulch), followed by T2 and T1 treatments (209.39 cm, 0.37, 12.5, 72.48 cm, 4.62 cm, 1.50, 15.03 cm, 4.44 cm, 202.19 g, 421.56 g, 111.55 g, 26.46 g, and 8.35 t/ha). Among the various tree leaf mulch treatments, it was found that the Kalo koroi tree leaf mulch performed better for vegetative growth, yield, and yield-contributing attributes in maize compared to the no mulch treatment. Therefore, it was suggested that tree leaf mulches could be a potential alternative to traditional mulches in maize cultivation. Res. Agric. Livest. Fish. Vol. 11, No. 2, August 2024: 205-214

The Effect of Mycorrhiza and Plant Growth-Promoting Rhizobacteria Supplementation on Zea mays saccharata Sturt. Growth and Productivity Grown on Low Nutrients Soil

Marginal land has low nutrient content (nitrogen, phosphorus, potassium). Addressing nutrient deficiencies on marginal land requires a strategic approach. Biological fertilizers like Arbuscular Mycorrhizal Fungi (AMF) and plant growth-promoting rhizobacteria (PGPR) enhance nutrient availability through symbiotic interactions. In addition, organic fertilizers such as compost could provide organic matter and improve soil structure to increase plant growth and productivity. Combining these three fertilizers with the addition of low doses of NPK fertilizer can increase the growth and productivity of maize crops on sub-marginal land. This study aims to determine the effect of AMF, consortium of PGPR, and a low dose of NPK on the growth and productivity of maize and soil nutrients on sub-marginal land by measuring plant growth up to 8 WAP (week after planting) (parameters: plant height, stem diameter, number of leaves, leaf area, chlorophyll content, stomatal density) and productivity (parameters: cob length, cob weight with husk, fresh weight, dry weight) and levels of N, P, and K elements at 8 WAP in the soil after planting. All treatments showed an increase in the level of N and K elements, while the P element showed a decrease compared to the control (soil without treatment). Moreover, each parameter did not show a significant difference, but the P2 (Compost + PGPR consortium + AMF + 50% of NPK) treatment showed the best growth and productivity. Overall, the data showed the utilization of PGPR and AMF combination was able to reduce the usage of chemical fertilizer by 50%.

Response of N uptake, N-total and yield of sweet corn (Zea mays saccharata Sturt) due to fertilization with granulated solid organic fertilizer and NPK in Inceptisol soil

Sweet corn productivity is greatly influenced by proper cultivation techniques, of which fertilization is one of the main factors. Effective fertilization not only supports plant growth but also affects nutrient uptake and yield. This study aimed to evaluate the effect of granulated solid organic fertilizer and NPK fertilizer on nitrogen (N) uptake, soil N-total content, and sweet corn yield in Inceptisol soil. The research was conducted from February to June 2024 at the Experimental Field, Faculty of Agriculture, Padjadjaran University with treatments including control, NPK fertilizer, and various combinations of granular organic fertilizer and NPK. The results showed that the combination of granule organic fertilizer and NPK significantly increased nitrogen uptake and N-total content in the soil compared to the single NPK application. In addition, sweet corn yield, as measured by cob weight per plant, per plot, and per hectare, also increased significantly with the fertilizer combination treatment. This study supports the use of fertilization strategies that integrate organic and inorganic fertilizers as an effective way to increase sweet corn productivity on soils with limited fertility, such as Inceptisol. The application of a combination of 1 NPK + 1 granulated organic fertilizer was the best combination in increasing N uptake, N-total and sweet corn yield.

Investigating the properties and agronomic benefits of onion peel and chicken feather-derived biochars

Biochar production from unconventional biomass, specifically onion peel (OP) and chicken feathers (CF), was investigated in this study. Two distinct biochars were produced by doping each biomass with the other, with the aim of exploring the synergistic effects of different feedstock combinations on biochar properties. The biochar production process was conducted using a retort heating method and characterized using several techniques. A yield of 36 % was obtained for OP-doped biochar (OP92CF8-BC) and 23 % for CF-doped biochar (F92OP8-BC). Fourier Transform Infrared Spectroscopy analysis revealed characteristic functional groups from cellulose, hemicellulose, and lignin in OP92CF8-BC, while CF92OP8-BC displayed keratin-related peaks. Scanning Electron Microscopy imaging showed surface morphology differences, with OP92CF8-BC exhibiting a rougher and more porous structure compared to CF92OP8-BC. Energy-Dispersive X-ray Spectroscopy analysis confirmed the elemental composition, with OP92CF8-BC having higher carbon, calcium, and sulfur contents and CF92OP8-BC having higher nitrogen and oxygen contents. The biochar had specific surface areas of 342.4 and 200.80 m2/g for OP92CF8-BC and CF92OP8-BC, respectively. According to the results, using biochar treatments-more especially, CF92OP8-BC-can significantly enhance cob weight. This could be good for agricultural productivity. These findings highlight the influence of feedstock composition on the properties of biochar and provide insights for its potential applications in soil amendment and pollutant removal.

THE EFFECT OF OIL PALM EMPTY FRUIT BUNCH BIOCHAR AND CHICKEN MANURE BIOCHAR ON NUTRIENT UPTAKE OF N, P, K AND YIELD OF SWEET CORN ON ALLUVIAL LAND

Alluvial land which is very wide in the West Kalimantan region can be used as land for the cultivation of sweet corn. Low organic matter in alluvial soils requires fixing agents to improve soil structure. This study aims to determine the effect of giving a combination of tankos biochar and chicken manure biochar on dry weight, nutrient uptake of N, P, K and weight of cobs with sweet corn husks. This research was conducted from November to April, in the experimental garden of the Faculty of Agriculture, Tanjungpura University, Pontianak City, West Kalimantan. This study used a completely randomized design (CRD) consisting of 5 treatments and 5 replications consisting of 25% tankos biochar and 75% chicken manure biochar: B0 (Control), B1 (20 tonnes/ha), B2 (40 tonnes/ ha), B3 (60 tonnes/ha), B4 (80 tonnes/ha). The results showed that the administration of a combination of tankos biochar and chicken manure biochar had a significant effect on all parameters. Giving a combination of tankos biochar and chicken manure biochar. Giving a combination of tankos biochar and chicken manure biochar had a very significant effect on the parameters of dry weight and weight of corn cobs and husks. The best treatment or dosage for all parameters lies in treatment B4 (80 tons/ha) which gives a 3.7% increase in dry weight, N absorption is 1.3%, P absorption is 1.45%, K absorption is 0.25% , the weight of cobs with husks was 1.88% % and the yield of sweet corn was 10.40 tonnes/ha.

Impact of Trichoderma afroharzianum infection on fresh matter content and grain quality in maize.

Trichoderma afroharzianum, a ubiquitous soil-borne fungus found on plant roots and decaying residues, displays competitive traits and mycoparasitic behavior against diverse microorganisms. Selected strains of this fungus are known in agriculture for their beneficial effects on plant growth and as bio-fungicides. However, recent findings have pinpointed Trichoderma afroharzianum as the causal agent behind maize ear rot disease in Europe since 2018, notably impacting maize cobs in Germany, France, and Italy. This study aims to evaluate the severity of Trichoderma ear rot disease on maize fresh matter content and specific quality parameters under semi-field conditions. Two distinct maize varieties were artificially inoculated with a pathogenic Trichoderma isolate at the flowering stage using needle pin or silk channel methods. Disease severity was assessed visually at the time of harvest based on the percentage of infected kernels according to EPPO Guidelines (PP 1/285). Fresh matter content and quality parameters such as alpha-amylase activity, C/N ratio, water, and sugar content were analyzed. Results showed that needle pin inoculation led to higher disease severity (60%) compared to silk channel inoculation (39%). Cob weight decreased significantly at the highest disease severity level by up to 50% compared to control plants. In both varieties, alpha-amylase activity increased significantly with higher Trichoderma disease severity, resulting in starch degradation and increased glucose release. The germination rate was severely affected by the infection, with only 22% of grains germinating, and the seedlings showed shortened and deformed growth. This is the first report on Trichoderma ear rot infection and its effect on fresh matter content and quality parameters in maize after artificial inoculation under field conditions. The results address an important knowledge gap and provide valuable insights into the infection pathway and impact on maize quality.

BIOMETRIC PARAMETERS IN THE CHARACTERIZATION OF EARS IN A COLLECTION OF CORN GENOTYPES

The study evaluated morphological parameters and yield elements in corn ears to compare a collection of corn genotypes. The research took place in ARDS Lovrin, Romania. 80 maize genotypes were analyzed, and certain representative parameters were determined: corn ear weight (CEW, kg), corn grain weight (CGW, kg), corn cob weight (CCW, kg). Based on the recorded values, the kernels in corn ears was calculated (KCE, %). Several ratios were also calculated, CEW/CGW, CEW/CCW, and CGW/CCW. The data series showed normal distribution and statistical confidence. Very strong positive correlation was recorded between CGW and CEW (r = 0.963), and between the ratios CGW/CCW and CEW/CCW (r = 0.996). Very strong negative correlation was registered between the ratio CEW/CGW and KCE(%), r = -0.992. According to PCA, PC1 explained 69.055% of variance, and PC2 explained 29.108% of variance. The close correlation of the Lv_47 hybrid with the KCE parameter (%) was observed. According to the cluster analysis, the dendrogram for the classification of genotypes based on similarity, in relation to the KCE parameter resulted (Coph.corr. – 0.813). The variation of the KCE parameter (%) in relation to the CEW, CGW, and CCW parameters was analyzed by regression analysis. Mathematical models described the variation of KCE in relation to the considered morphological parameters, under statistical safety conditions (R2 = 0.999 in relation to CEW and CGW; R2 = 0.757 in relation to CEW and CCW; R2 = 0.835 in relation to CGW and CCW; p <0.001 for all cases). Graphical models (3D, isoquants) represented the KCE variation (%) in relation to the considered morphological parameters. The divergent influence was recorded in the case of the CGW and CCW parameters on the KCE distribution.

Hubungan varietas dengan pemangkasan daun terhadap pertumbuhan dan produksi tanaman Jagung manis (Zea mays saccaratha Sturt)

The research was conducted in the experimental garden of the Faculty of Agriculture, Riau Islamic University, Pekanbaru, within 3 months from March to May 2023. This study aims to determine the interaction effect and the main effect of the Relationship between Variety and Leaf Pruning on the Growth and Production of Sweet Corn Plants (Zea mays saccaratha Sturt). This study used a Divided Plots Design (RPT), the main plot was variety and the subplots were pruning. The variety treatment consisted of 4 treatment levels and pruning consisted of 4 treatment levels, so there were 16 treatment combinations with 3 replications. This study consisted of 48 experimental units. Each experimental unit consisted of 4 plants and 2 sample plants, a total of 192 plants. The parameters observed were plant height, age of male flower emergence, weight of cob with cob, length of cob without cob, number of rows in one cob. Observational data were analyzed statistically and conducted with the Honest Real Differences (BNJ) Further Test at the 5% level. The results showed that the interaction relationship between varieties and leaf pruning had a significant effect on all observation parameters. The best treatment was the panglima variety and pruning the lower 1/3 of the leaves. The main plot treatment significantly affected all observation parameters. The best treatment is the panglima variety. The treatment of subplots significantly influenced all observation parameters. The best treatment is leaf pruning 1/3 of the lower leaves.

Maize production at phenological stages affected by water irrigation stress in dryland conditions

Abstract The growth and yield of maize are significantly influenced by the adequacy of soil moisture during the growth period. Given the uncertain rainfall due to climate change, the availability of water for maize production is becoming increasingly limited, while the demand is rising due to population growth. The extent to which maize yield is affected by soil moisture stress at each phenological stage in dryland areas has not been thoroughly explored. This study aimed to determine the production and biomass of maize at various growth stages due to water stress. Watering using drip irrigation equipped with soil moisture sensors was stopped after the maize plants reached 20, 40, 60 (flowering), 80 days after sowing (DAS), and at harvest. Parameters of biomass, maize yield, and other parameters were determined when the soil’s permanent wilting point reached, and soil samples were taken to determine the moisture content. The results showed that irrigation up to 80 DAS was not significantly different in yield, although it was 30% lower than that irrigation up to harvest. However, irrigation up to 60 DAS reduced the yield by 3.9 times and 4.9 times compared to the yield at irrigation up to 80 DAS (85.897 grams/plant) and at harvest (108.57 grams/plant), respectively. Other parameters, such as dry biomass, cob weight, cob length, and cob diameter followed the yield trend, although their values varied. The dry biomass of maize at irrigation until 20 and 40 DAS were 13.68 grams/plant and 40.05 grams/plant, respectively. The experiment implies that irrigation water should be provided until 80 DAS to minimize significant yield losses of maize in dryland conditions.

Growth and Yield Responses of Bari Sweet Corn-1 (Zea Mays L.) to Naa at Different Nitrogen Levels

A field experiment was conducted to investigate the effect of foliar application of NAA at varying N-levels on growth and yield responses of BARI Sweet Corn-1 (Zea mays L.). The trial consisted of ten treatments viz. control = without NAA and N fertilizer; RDN (recommended dose of N fertilizer); 25 ppm NAA + RDN; 50 ppm NAA + RDN; 25 ppm NAA + 50% higher RDN; 50 ppm NAA + 50% higher RDN; 25 ppm NAA + 100% higher RDN; 50 ppm NAA + 100% higher RDN; 25 ppm NAA+ 150% higher RDN and 50 ppm NAA + 150% higher RDN. Results showed that application NAA in combination with various nitrogen (N) levels produced better growth than control but with few exceptions. Growth parameters viz. total dry mater (TDM), leaf area (LA), relative growth rate (RGR) and net assimilation rate (NAR) were recorded maximum from 25 ppm NAA in combination with RDN treatment. Findings revealed that 25 ppm NAA in combination with RDN treatment had also produced higher number of leaves per plant, specific leaf area (SLA), biomass duration (BMD) and absolute growth rate (AGR) than RDN treatment although statistically at par to each other. The maximum number of leaves per plant, shoot-root ratio and SLA although recorded maximum from 25 ppm NAA in combination with 100% higher RDN treatment but statistically similar to rest of the combined treatments. Yield attributes and yield of BARI Sweet Corn-1 showed positive response to NAA at varying N-levels with significant variations in majority of cases. The maximum number of cobs and productive cobs per plant, dry weight of cobs, length of cob, number of seed per row and cob, dry weight of tassel, yield per plant and harvest index were also obtained from 25 ppm NAA in combination with RDN treatment. However, maximum number of cobs and productive cobs per plant were also noted from 25 ppm NAA in combination with 100% higher RDN treatment. Significantly maximum yield per plant (114.41g) obtained from 25 ppm NAA in combination with RDN treatment which was 12.02% higher over RDN treatment. Out of ten treatments, foliar application of 25 ppm NAA in combination with RDN treatment produced better stimulation in growth and yield of BARI Sweet Corn-1. Bangladesh J. Bot. 53(2): 337-344, 2024 (June)

Chitosan nanofertilizer to strengthen sink strength and provide resistance against PFSR (post flowering stalk rot) disease in maize

We herein report a significant increase in sink strength and disease resistance in maize crop using copper-salicylic acid co-encapsulated chitosan nanofertilizer in seed treatment and foliar application. These chitosan nanofertilizer (0.01–0.16%) exhibited significant antifungal activity against post-flowering stalk rot (PFSR) in pot house [45.2–73.5% (mycelia growth) and 40.0–79.6% (spore germination)]. In field conditions, chitosan nanofertilizer (0.01–0.16%) effectively controlled the PFSR disease with PEDC (percentage efficacy of disease control) values of 68.6–93.8%. The results are evident with the significant improvement in defence enzyme activities namely phenylalanine ammonia lyase (PAL, 4.9 fold increase) and polyphenol oxidase (PPO, 2.3 fold increase). Crop growth parameters namely plant height, ear height, cob weight, test weight, grain yield/plot and biomass were also significantly improved. The grain yield increased by 1.8 fold proving that up-regulated source activity is coupled with elevated sink strength. Overall, we claim that the developed chitosan nanofertilizer serves both as a fertilizer as well as a pesticide. The developed fertilizer has agricultural importance and could be tested for its potential use in other crops.

The use of fixed shelling percentage biases genotype selection in hybrid maize multi-environment yield trials

Context or problemPhenotyping is an integral part of plant breeding operations. In many cases the trait measured is not identical to the target trait for reasons of speed and or cost. This is a form of indirect selection, where correlation between the trait measured and the target phenotype influences the rate of genetic gain. Low correlations lead to slow rates of genetic gain. In sub-Saharan African maize breeding programs, maize grain yield in breeding experimental plots is measured as a field weight (FW), which includes the grain and cob. The weight of grain from each plot is estimated as a standard proportion of grain to total ear weight using a shelling percentage of 80 %. This approach assumes that there is no genetic, environment or genetic by environment interaction in shelling percentage which, if present, would contribute to slower rates of genetic gain for grain yield. Objective or research questionThis study investigated the magnitude of genetic and environmental variation in shelling percentage and its impact on selection in six hybrid maize multi-environment yield trials in Ethiopia over two seasons. MethodsThe data of shelled grain weight (SW) and cob weight (CW) from the trials were analyzed using a bivariate linear mixed model. ResultsGenetic variances for both traits varied across the six testing sites ranging from 0.199 to 2.975 for SW and from 0.029 to 0.245 for CW. The genetic correlations between pairs of sites for SW and CW also varied, indicating the existence of genotype by environment interaction for these traits. Additionally, the bivariate regressions between FW and SW indicated there was substantial genetic deviation around the 80 % shelling response, and this relationship was impacted by environmental influences. ConclusionThe use of a constant relationship of 80 % shelling biases grain yield prediction in multi-environment hybrid maize yield trials and thus reduces the rate of genetic gain in maize breeding programs. Implications or significanceTaking into account the variations in the shelling percentage of the genotypes across sites in predicting grain yield from field weight improves the accuracy of genotype selection and the rate of genetic gain in maize breeding programs.

Potential of Neem (Azadirachta indica) Extract in Managing Fall Armyworm on Maize

This research assessed the effect of neem leaf extract on the larval population of the fall armyworm and the level of damage, growth, and yield of maize. A Randomized Complete Block Design (RCBD) with four treatments (Control, 50 g per L, 100 g per L and 200 g per L of neem leaf extract) applied within the two seasons of 2022A and 2022B. The findings showed that a higher concentration (200 g per L) of neem leaf extract-treated maize plants registered the least leaf damage (0.15), severity (0.15), and larvae population (0.1). This effect was most attained during the 1st season of maize production and at the earliest vegetative weeks of maize growth (3 WAP to 5 WAP, i.e., weeks after planting). The higher neem leaf extract concentration of 200 g per L produced the most significant (p < 0.001) effect on maize growth traits. A higher plant height (162.51 cm), longer leaf length (112.5 cm), wider leaf width (11.7 cm), and broader stem girth (11.91 cm) were attained under 200 g per L of neem leaf extract treated plots during the 1st season of maize production and 11 WAP. The findings of this showed that a relatively high concentration of neem leaf extract produced a higher cob weight (200 g per L = 180.1 g) followed by 100 g per L (174.1 g), 50 g per L (140.9 g) and control (139 g). The weight was optimised during the 1st season of maize production (163.8 g). The grain yield was higher under 200 g per L (153.7 g) of neem extract. The above findings demonstrated that a high concentration of neem leaf extract reduced fall armyworm infestation and increased maize plant growth and yield. Farmers should, therefore, be encouraged to apply 200 g per L of neem leaf extract in the management of fall armyworms and improve plant growth and yield because it contains antifeedant and insecticidal properties against the fall armyworm.

Level of Resistance of S1 Lines of Corn Plants to Drought Stress

The formation of hybrid varieties by self-crossing the F2 population has been carried out, thus obtaining the first generation selfing line (S1). This research aims to determine the level of drought stress resistance of S1 lines and corn plants and the correlation between their characters and the ISC value for each stress. The method used is an experimental method with field experiments. The experiment was carried out from March to June 2023 at the location in Gumantar Village, Kayangan District, North Lombok Regency. The experimental design used was a randomized block design (RAK) in a split plot design with the main plot consisting of stress and normal treatments, while the sub plots were the S1 lines and the F2 population. The results showed that there were different levels of resistance in the S1 line. G27 has resistance with tolerant criteria, 13 lines are moderately tolerant, and 16 other lines are susceptible; Correlation criteria between characters vary with the ISC value in each stress and normal condition. Characters that are strongly correlated with the ISC value are chlorophyll A, total chlorophyll, harvest dry cob weight, and dry kernel weight. The formation of S2 lines can be done using tolerant and moderately tolerant lines.

Potassium Management for Corn Growth, Yield and Sweetness under Sabah Sandy Soil

A study was conducted to determine the effect of potassium (K) with organic fertilizers on the growth, yield and sweetness of reddish waxy corn. The treatments were: (T1) standard fertilizer rate of 60 kg ha-1 K2O without organic fertilizer (control); (T2) 30 kg ha-1 K with organic fertilizer; (T3) 90 kg ha-1 K with organic fertilizer and (T4) 120 kg ha-1 K with organic fertilizer. Organic fertilizer used was 1.5 t ha-1 Bokashi and 20 t ha-1 chicken manure biochar (CMB). The planted corn received 120 kg ha-1 N and 60 kg ha-1 P2O5. The experimental design was Completely Randomized Design (CRD) with six replications. Stem girth, number of leaves, the height of the first cob, fresh weight of the first cob, 100 grains weight, cob girth, cob length and sweetness (Brix scale, %) data were analyzed using ANOVA (Analysis of Variance) at 5% significant levels. The Least Significant Different (LSD) was used to compare the means for significantly different results. Significant differences in growth were obtained at (p<0.05) in waxy corn for the number of leaves, the height of the first cob, length of cob, and girth between the control and all treatments. However, there is no significant difference for the sweetness of waxy corn for all treatments. Mean total for growth parameters; the number of leaves, stem girth and height of the first cob from soil surfaces and mean total for yield parameters; cob girth, length of cob, fresh weight of cob, 100 grains weight and the number of kernels was significantly higher for all treatments of T2, T3 and T4 compared to control the treatment of T1. The study showed no significant difference in the sweetness of waxy corn with increasing potassium application, resulting in increased total soluble content. Similar studies for a different rate of organic fertilizers and soil analysis can be done to ascertain further the effects on growth, yield, and sweetness parameters of reddish waxy corn with selected soil properties.