June Sowing Research Articles

Influence of Tree Geometry on Growth and Yield of Mungbean (Vigna radiata L.) under Gamhar (Gmelina arborea Roxb.) based Agroforestry System

The experiment was conducted during kharif (June to September) 2022–23 at Rani Lakshmi Bai Central Agricultural University, Jhansi, Uttar Pradesh, India to evaluate effect of Gmelina arborea geometry on the growth and yield of mungbean, tree growth, biomass, carbon storage and assessing the economic feasibility of the agroforestry systems. The experiment was designed for intercropping of one mungbean high yielding varieties viz., IPM 205-7 (Virat) sown in June with Gmelina arborea. The treatments for gamhar and mungbean are as follows: T1-Vigna radiata sole crop; T2-Gmelina arborea sole tree (5×5 m2); T3-Gmelina arborea sole tree (5×4 m2); T4-Gmelina arborea sole tree (5×3 m2); T5-Gmelina arborea (5×5 m2)+Vigna radiata; T6-Gmelina arborea (5×4 m2)+Vigna radiata; T7-Gmelina arborea (5×3 m2)+Vigna radiata. Experiment was designed in randomized block design (RBD) with seven treatments and five replications. The effect of different spacing patterns viz., S1-5×5 m2, S2-5×4 m2, S3-5×3 m2 in 2 year old Gamhar plantation with seven treatments combinations on mungbean was studied at the Forestry Research Farm, RLBCAU, Jhansi. The maximum number of branches plant-1 (8.04), number of trifoliate leaves plant-1 (11.96), number of seeds pod-1 (12.32), grain yield (0.73 t ha-1) and straw yield (2.13 t ha-1) was recorded in mungbean sole crop. The plant height (62.51 cm) was recorded highest in mungbean intercrop in 5×3 m2 gamhar spacing. The maximum girth (27.38 cm) of trees was recorded in 5×5 m2 gamhar spacing mungbean intercrop. The tree height (6.01 m) and benefit cost ratio (2.67) was observed maximum in 5×4 m2 gamhar spacing with mungbean intercrop.

Effect of Different Sowing Windows on Dry Matter Accumulation of Pigeonpea Genotypes

A field experiment was conducted to study the “Effect of different sowing windows on dry matter accumulation of pigeonpea genotypes” at Regional Agricultural Research Station, Vijayapura, during Kharif 2021. The experiment was laid out in a split-plot design assigning four sowing windows to main plots viz., first fortnight of June (23-24th SMW), second fortnight of June (25-26th SMW), first fortnight of July (27-28th SMW) and second fortnight of July (29-30th SMW), whereas genotypes to subplot viz.,TS-3R, GRG-152 and GRG-811 and replicated thrice. The results revealed that sowing in first fortnight of June accumulated more dry matter in leaves (18.47 g plant-1), stem (131.22 g plant-1) and reproductive parts (68.16 g plant-1). Among the genotype GRG-152 accumulated higher dry matter in leaves (17.34 g plant-1) and stem (123.01 g plant-1). However, dry matter accumulation in reproductive parts is higher in TS-3R (63.68 g plant-1). Similarly TDMP was higher in first fortnight of June sowing (217.85 g plant-1) than delayed sowing in second fortnight of July. TS-3R accumulated higher TDMP in the beginning growth stage when compared to GRG-152 and GRG-811. However, TDMP was higher in GRG-152 at later stage. This study revealed that pigeonpea sown in first fortnight of June recorded higher dry matter production and it’s partitioning in leaf, stem and reproductive parts and among the genotype TS-3R recorded significantly higher dry matter in pods due to more photosynthetic activity of the genotype which results in higher yield of the crop.

Seed Yield, Yield Components, and Damaged Seed Rate in Soybean Sown in June and July in Kanagawa Prefecture

Seed Yield, Yield Components, and Damaged Seed Rate in Soybean Sown in June and July in Kanagawa Prefecture

Modelling the climate change impact of mitigation (RCP 2.6) and high emission (RCP 8.5) scenario on maize yield and possible adaptation measures in different agroclimatic zones of Punjab, India.

A simulation study was performed for assessing climate change impact on maize under Representative Concentration Pathways (RCPs 2.6 and 8.5) for Punjab, India. The study area comprised of five agroclimatic zones (AZs) including seven locations. The bias corrected temperature and rainfall data from four models (CSIRO-Mk-3-6-0, FIO-ESM, IPSL-CM5A-MR and Ensemble) were used as input in CERES-Maize model which was run with constant management practices for two Punjab maize hybrids (PMH1 and PMH2). The maize yield for upcoming 70 years (2025-2095) was simulated and its deviations from the baseline (2010-2021) yield were computed under optimized sowing (early May to early July) and current sowing (end May to end June) period. With current sowing dates, the maize yield declined under both RCP2.6 and RCP8.5 scenarios, respectively in all the AZs, i.e. by 4-23 and 60-80% in AZII, by 5-60 and 60-90% in AZIII, by 9-30 and 50-90% in AZIV and by 13-40 and 30-90% in AZV. Though yield decline was lesser under RCP2.6 as compared to RCP8.5, but still it indicates that adaptive strategy such as shifting of sowing dates may be helpful in stabilizing the maize yield. The results for iterative combinations of sowing period revealed that early June sowing in AZ II for both the hybrids, mid to end June (Ludhiana and Amritsar) and end May to mid June (Patiala) sowings for PMH1 were able to nullify the negative impact of climate change. Maize cultivation in AZIV and AZV would not be a suitable venture for farmers of the region. This article is protected by copyright. All rights reserved.

Production potential, quality and thermal utilization of fodder pearl millet varieties under different sowing environments in irrigated conditions of central Punjab in India

An experiment was conducted at Punjab Agricultural University, Ludhiana, India during two consecutive years i.e., 2019 and 2020 to study the effect of dates of sowing and pearl millet varieties on productivity and quality of green fodder and thermal utilization by the crop. The field experiment was laid-out in a split plot design with seven dates of sowing (1st April, 15th April, 1st May, 1st June, 15th June, 1st July and 15th July) in main plots and two varieties of pearl millet (PCB 165 and FBC 16) in sub plots with three replicates. Significantly highest green fodder yield (69.3 t/ha) was obtained with 1st June sowing which was probably on account of maximum plant height and number of tillers. The 1st June sown crop also recorded significantly highest dry matter and crude protein yield of 15.0 t/ha and 0.95 t/ha, respectively. Both advanced and delayed sowings recorded significant reduction in green fodder and dry matter yield. The crop sown on 1st May required maximum growing degree days, photo-thermal and helio thermal units at 50% flowering stage and sowing done early as well as late recorded significant reduction in these agro-climatic indices. Across different dates of sowing, PCB 165 registered an increase of 11.9 and 12.4% in green fodder and dry matter yields, respectively over FBC 16 due to higher accumulation of growing degree days, photo-thermal and helio thermal units for 50% flowering stage. The interaction effect showed that PCB 165 sown on 1st May, 1st and 15th June recorded significantly more green fodder yield over FBC 16, while the differences were narrow and non-significant at other dates of sowing.

Genetic variability predicting breeding potential of upland cotton (Gossypium hirsutum L.) for high temperature tolerance

BackgroundHigh temperature stress at peak flowering stage of cotton is a major hindrance for crop potential. This study aimed to increase genetic divergence regarding heat tolerance in newly developed cultivars and hybrids. Fifty cotton genotypes and 40 F1 (hybrids) were tested under field conditions following the treatments, viz., high temperature stress and control at peak flowering stage in August and October under April and June sowing, respectively.ResultsThe mean squares revealed significant differences among genotypes, treatments, genotype × treatment for relative cell injury, chlorophyll contents, canopy temperature, boll retention and seed cotton yield per plant. The genetic diversity among 50 genotypes was analyzed through cluster analysis and heat susceptibility index (HSI). The heat tolerant genotypes including FH-Noor, NIAB-545, FH-466, FH-Lalazar, FH-458, NIAB-878, IR-NIBGE-8, Weal-AG-Shahkar, and heat sensitive, i.e., CIM-602, Silky-3, FH-326, SLH-12 and FH-442 were hybridized in line × tester fashion to produce F1 populations. The breeding materials’ populations (40 F1) revealed higher specific combining ability variances along with dominance variances, decided the non-additive type gene action for all the traits. The best general combining ability effects for most of the traits were displayed by the lines, i.e., FH-Lalazar, NIAB-878 along with testers FH-326 and Silky-3. Specific combining ability effects and better-parent heterosis were showed by the crosses, viz., FH-Lalazar × Silky-3, FH-Lalazar × FH-326, NIAB-878 × Silky-3, and NIAB-878 × FH-326 for seed cotton yield and yield contributing traits under high temperature stress.ConclusionHeterosis breeding should be carried out in the presence of non-additive type gene action for all the studied traits. The best combiner parents with better-parent heterosis may be used in crossing program to develop high yielding cultivars, and hybrids for high temperature stress tolerance.

Effect of Sowing Season, Age and Height of Cutting of the Primary Crop of Sorghum bicolor cv. ‘Abu Sabeen’ on Growth and Forage Yield of the Secondary Crop

A field experiment was conducted for two consecutive seasonsat the Gezira Research Farm to study the effect of growing season, ageand height of cutting of the primary crop of ‘Abu Sabeen’, on theregrowth yield. The first experiment was sown on 4th of September 2005and the second was on 7th of June 2006.The treatments comprised cuttingthe primary crop at 5 ages i.e. 6, 7, 8, 9 and 10 weeks from sowing and 4cutting heights i.e. 5, 10, 15 and 20 cm above ground. The 20 treatmentswere allotted to a randomized complete block design with 3 replications.Data were collected on weather conditions, forage yield, plant height, andculm density of the first regrowth. The growing season was crucial formultiple -cut crop of ‘Abu Sabeen’; long days and high temperature beingmore conducive for high dry matter yield of the regrowth mainly throughthe increase in plant height, and shorter days and relatively lowertemperature being conducive for high culm density and retarded growth.Taller plants were determinant of the regrowth yield than the increase inthe culm density. Highest dry matter yields of the regrowth wereassociated with June sowing and cutting the primary crop at the age of 7weeks and cutting height of 15 or 20 cm above ground.

Effects of temperature and light conditions during the late growth stage on delayed stem senescence and cytokinin levels in the xylem exudate of soybean

AbstractDelayed stem senescence (DSS) in soybean plants is defined as retarded leaf and stem maturity, even if pods mature normally. This phenomenon is a serious problem for the combine harvesting of soybean in Japan. Our previous research showed that DSS occurred more frequently in June sowing than in July sowing, and the plants sown in June were exposed to higher temperature and higher solar radiation intensity during reproductive growth stage as compared to those sown in July. We additionally observed higher levels of cytokinins, plant hormones with senescence inhibition activity, in xylem exudate after pod‐setting stage (R4) under the DSS‐induced condition. Thus, this study investigated the effects of the respective environmental factors, temperature and light intensity, after R4 on cytokinin levels in the xylem exudate and the occurrence of DSS. Pot experiments were conducted in the experimental field of Nihon University (Fujisawa‐city, Kanagawa, Japan). In temperature treatments, soybean plants grown in the field environment were moved to an air‐conditioned room at R4 stage, whereas control of light intensity was achieved by shading using cheese clothes under the field condition. The temperature control experiments revealed that high temperature after R4 promoted the DSS symptom, while low temperature after R4 inhibited the occurrence of DSS. On the other hand, decreased light intensity after R4 did not affect the severity of DSS. The cytokinin levels in the xylem exudate at R5 correlated with the severity of DSS in the temperature treatments, but the change in light intensity did not influence the cytokinin levels. These results indicated that high temperature after pod‐setting stage have a profound effect on the occurrence of DSS, and this effect is mediated by the increased cytokinin levels in the xylem exudate.

The impact of seasonal variation on occurrence of Fusarium root rot diseases, fly infestations, weeds, herbicide application and yield

Effects of cultivar, herbicide and sowing date on bean fly, Fusarium root rot, weed and productivity were examined during 2015 and 2016 seasons using a split-split-plot design. Sowing delayed from 10-15 May (mid spring) to 25–30 June (early summer) reduced weed biomass up to 49% (2015) and 78% (2016) at flowering, and 79% at maturity in control plots. Herbicides decreased weed biomass up to 79% (2015) and 63% (2016) for first-date sowings of COS16 and Talash cultivars at maturity compared to control. Late June sowings decreased disease incidence up to 75% at maturity. Late sowings indicated greater fly infestation and shorter bean plants compared to earlier sowings. Low 100-seed weight and yield (kg/ha) of bean cultivars were obtained for early sowings. This research advised late sowing of beans in late spring to minimize Fusarium root rot, herbicide applications and weed threats, and improve 100-seed weight and yield for sustainable production.

Thermal and radiation environments for assessing crop-weather relationship of soybean in eastern Madhya Pradesh

A field experiment was conducted during with three sowing dates (23 June, 8 July and 23 July) with three varieties (JS 20-29, JS 20-34 and JS 97-52) kharif season of 2016 and 2017 at Jabalpur in eastern Madhya Pradesh for assessing crop weather relationship in soybean through thermal and radiation environments. The results revealed that early sown crop attained more accumulated heat units, and yield decreased with delay in sowing. The maximum and minimum temperatures during reproductive stage were positively correlated with seed yield while negatively associated with vegetative and pod development stages. Photosynthetic active radiation absorption (APAR) was maximum in June sowing in semi-determinate JS 97-52 variety at pod formation stage. Maximum leaf area index (LAI) exhibited in June sown for JS 97-52 variety during pod formation stage. Seed yield increase with increased in APAR and LAI during pod formation stage. Season length difference between normal and actual crop maturity period increased with the decrease in GDD thereby suggesting a decline in yield due to shortening of crop growing period.

Yield Improvement and Nutrient Uptake of Little Millet (Panicum sumatrense) for Agronomic Interventions

Field experiments were conducted during kharif, 2019 and kharif 2020 at S.V. Agricultural College Farm, Tirupati with three different times of sowing of little millet (second fortnight of June, first fortnight of July and second fortnight of July) in combination with three methods of establishment (Broadcasting, Sowing at 30 cm × 10 cm and transplanting 20 days old seedlings) and three nitrogen levels (20 kg N ha-1, 30 kg N ha-1 and 40 kg N ha-1). The results of the experiment revealed that among the three times of sowing, second fortnight of June sowings recorded higher grain yield, straw yield and nutrient uptake of little millet while lower values of these were obtained with July second fortnight sown crop during both the years of study. Transplanted little millet resulted in superior grain yield, straw yield and nutrient uptake compared to broadcasting and sowing at 30 cm × 10 cm. Maximum values of grain yield, straw yield and nutrient uptake were observed with application of 40 kg N ha-1 while minimum values of these parameters were obtained with application of 20 kg N ha-1. Transplanting little millet during second fortnight of June along with the application of 40 kg N ha-1 achieved higher grain and straw yield besides nutrient uptake by grain.

Performance of Winter-Sown Cereal Catch Crops after Simulated Forage Crop Grazing in Southland, New Zealand.

(1) Background: Winter grazing of livestock poses significant environmental risks of nitrogen (N) leaching and sediment runoff. (2) Methods: A field study tested the effects of sowing catch crops of oats (Avena sativa L.), ryecorn (Secale cereale L.) or triticale (Triticosecale) in June and August (winter) in Southland, New Zealand (NZ), on the risk of N leaching losses from simulated N loads left after winter forage grazing. (3) Results: Catch crops took up 141–191 kg N ha−1 by green-chop silage maturity (approximately Zadoks growth stage 52; November/December). Importantly, early-sown catch crops were able to capture more N during the key leaching period from winter to mid-spring (77–106 kg N ha−1 cf. 27–31 kg N ha−1 for June and August treatments, respectively). At this time, ryecorn and triticale crops sown in June captured 20–29 kg ha−1 more N than June-sown oats (77 kg N ha−1). In October, early-sown catch crops reduced mineral N in the soil profile (0–45 cm depth) by 69–141 kg N ha−1 through the process of plant uptake. At green-chop silage maturity, catch crop yields ranged from 6.6 to 14.6 t DM ha−1. Highest yields and crop quality profiles (e.g., metabolizable energy, crude protein, soluble sugars and starch) were achieved by the oats, irrespective of the sowing date, indicating that trade-offs likely exist between environmental and productive performances of the catch crop species tested. (4) Conclusion: The catch crop of choice by farmers will depend on the desired end use for the crop, its place in the crop rotation and its potential for an environmental benefit.

Effect of Variety, Sowing Date and Location on Yield and Nutritional Characteristics of Sorghum

Sorghum is a forage species important in animal nutrition with an increased potential in the upcoming difficulties in agricultural practices in regard to climate change. Therefore, this paper describes its yield and nutritional parameters depending on growing conditions simulated on two locations (humid and fertile Obora, less fertile and dry Písky), two sowing dates (29. 5. and 25. 6.), and variety (11 varieties). Fresh matter yield was determined by weighing the sample on the field immediately after harvest, Dry matter yield and nutritional content were determined in laboratory by Weende analysis from dried and homogenized samples. Nutritional parameters measured were crude fibre, fat, nitrogen and ash content. Additionally, digestibility of organic as well as dry matter was determined. No significant differences in average fresh matter yield or dry matter yield were found between the two locations and sowing dates in general. There were significant differences among varieties, the highest yields were measured in KWS Zerberus (51.57 ± 3.76 t/ha of fresh matter yield, 15.98 ± 1.34 t/ha of dry matter yield, with higher values observed on Písky). Our data suggest, that sowing date does significantly affect fat content (higher in June sowing). Other nutritional parameters were also higher in sorghum sown in June, with the exception of ash. Nutritional composition of samples did not significantly differ variety to variety, however, there were differences in digestibility of the biomass. Organic matter digestibility was 70.58–85.67%, dry matter digestibility was 73.21–86.70%, with highest digestibility in DMS 45-480. Varieties with the highest importance to farmers in the area are KWS Zerberus, KWS Tarzan and KWS Kallisto (based on dry matter yield), and Triumfo BMR, Sweet Susana and DSM 45-480 (based on digestibility). Sorghum was able to perform well even on dry sandy soil with lower fertilization, which shows the high variability and suitability of sorghum in agricultural practice.

Phenological performance of groundnut under various sowing environment and planting density in hyper arid zone of Rajasthan, India

An experiment trial was conducted during three consecutive kharif seasons of 2017, 2018 and 2019 at three farmer’s field and Krishi Vigyan Kendra Farm, Bikaner (Rajasthan) to study the optimum time of sowing and planting density of groundnut. The experiment was laid out in split-plot design with four replications, comprising of nine treatments consisting of three date of sowing (15th May, 30th May and 15th June) as main plot treatments and three planting density (1.67 lac, 2.50 lac and 3.33 lac ha-1) as sub-plots. The results showed that significantly higher crop stand and plant height at harvest was observed in 15th June sowing than all other sowing dates, however, plant height remained at par with sowing at 30th May. Groundnut sown on 30th May recorded significantly higher periodic dry matter production, crop growth rate (CGR) and relative growth rate (RGR) as compared to early sowing on 15th May as well as late sowing on 15th June. Crop stand and plant height increased significantly with each increasing level of planting density (1.67 lac, 2.50 lac, and 3.33 lac ha-1) and the maximum was obtained at plant population of 3.33 lac ha-1. It was also observed that groundnut at planting density of 3.33 lac ha-1 remained statistically at par with planting density of 2.50 lac ha-1 and recorded significantly higher periodic dry matter production, crop growth rate and relative growth rate as compared to planting density of 1.67 lac ha-1.

Improving sorghum productivity under changing climatic conditions: A modelling approach

Climate variability and change will have far reaching consequences for smallholder farmers in sub-Saharan Africa, the majority of whom depend on agriculture for their livelihoods. Crop modelling can help inform the improvement of agricultural productivity under future climate. This study applies the Agricultural Production Systems sIMulator (APSIM) to assessing the impacts of projected climate change on two (early and medium maturing) sorghum varieties under different management practices. Results show high model accuracy with excellent agreement between simulated and observed values for crop phenology and leaf number per plant. The prediction of grain yield and total biomass of an early maturing variety was fair RMSEn (22.9 and 23.1%), while that of the medium maturing was highly accurate RMSEn (14.9 and 11.9%). Sensitivity analysis performed by changing the calibrated variables of key plant traits in the model, showed higher significant yield change by + or - 10 % changed in radiation use efficiency, (RUE), coefficient extinction (Coeff_ext) and Phyllocron (Phyllo) for early maturing variety while + or - 10 % changed in phyllochron and RUE showed a significant yield change for the medium maturing variety. Under climate change scenerios using RCP 8.5, the simulated yield for the early–maturing variety revealed high inter-annual variability and potential yield loss of 3.3% at Bamako and 1% at Kano in the near-future (2010–2039) compared to baseline (1980–2009). The mid-century (2040–2069) projected yield decline by 4.8% at Bamako and 6.2% at Kano compared to baseline (1980–2009). On the contrary, the medium maturing variety indicated significantly yield gain with high yielding potential in both climate regimes compared to the baseline period (1980–2009). The simulated grain yield increased by 7.2% at Bamako and 4.6% at Kano, in the near-future (2010–2039) while in the mid-century (2040–2069) projected yield increase of 12.3% and 2% at Bamako and Kano compared to baseline (1980–2009). Adaptation strategies under climate change for varying sowing dates in the near-future (2010–2039, indicated that June sowing had a higher positive yield gained over July and August sowing for early maturing variety; July sowing simulated positive gained by 5 -11% over June and August sowing for medium maturing variety in both locations. Similarly, under the mid-century (2040–2069), among the sowing dates and in both locations, June sowing indicates lowest negative yield change over July and August sowing for early maturing variety. However, for medium maturing variety, July sowing had the highest yield gain of 16% over June and August sowing at Bamako and June highest positive yield gained of 11.4% over July and August at Kano. Our study has, therefore, demonstrated the capacity of APSIM model as a tool for testing management, plant traits practices and adoption of improved variety for enhancing the adaptive capacity of smallholder farmers under climate change in the Sudanian zone of West Africa. This approach offers a promising option to design more resilient and productive farming systems for West Africa using the diverse sorghum germplasm available in the region.

Effect of intra-seasonal variation in temperature and rainfall on seed yield of pigeon pea cultivars using CROPGRO model

Three years (2014-15 to 2016-17) experimental data collected at Pulse Research Station, Vadodara was used to calibrate and validate the CROPGRO- pigeon pea model for three cultivars of pigeon pea (BDN 2, AGT 2 and Vaishali). The validated model was used to simulate the seed yield by changing the maximum and minimum temperature (-30 to +30C) in different months (June to January)and rainfall (-25% to +25%) during July, August and September. Results revealed that the elevated temperature had negative effect on seed yield and reduced temperature had positive effect. Among the varieties, AGT 2 was least affected by the temperatures and rainfall. Vaishali was found to be most sensitive to elevated temperature.Higher rainfall during August was beneficial on seed yield of pigeon pea. Pigeon pea sown in June was most affected due to elevated temperatures and July sown was most affected by rainfall. The effect of minimum temperature on seed yield was less than that observed with maximum temperature.

Effects of maturity genes E2 and E3 on yield formation in soybean cultivar Enrei in warm region, Fukuyama in Japan

ABSTRACTUnderstanding how maturity genes affect soybean yield formation will provide important information for crop management decisions. This study aimed to reveal how maturity genes E2 and E3 in the soybean cultivar ‘Enrei’ affect yields and yield formation in warm regions of Japan. ‘Enrei’ (e2e3) and three near-isogenic lines of ‘Enrei’ (e2E3, E2e3, and E2E3) were cultivated in 2016 and 2017 in Fukuyama, Japan (34°30′N, 133°23′E). Two sowing dates were set in each year (June sowing and July sowing). E2 extended the period from emergence to R1 and also the period from R1 to R7, whereas E3 extended only the period from emergence to R1. Interaction between E2 and E3 did not affect duration of the period from emergence to R1, but did affect the period from R1 to R7. Although seed yield did not differ between genotypes in the June sowings, the effects of E2 and E3 on seed yield in July sowing were both significant and interaction between E2 and E3 also observed. The total number of nodes increased in E3 genotypes in both sowing dates, especially in E2E3. Pod-set ratio was lower in E2 and E3 genotypes than in e2 and e3 genotypes in the June sowings, but did not differ between genotypes in the July sowings. The high yield of E2E3 genotypes in the July sowings was attributed to increased number of nodes and flower production while maintaining pod-set ratio. Appropriate choice of sowing date is suggested to be essential when using E3 genotypes.Abbreviations: HI: harvest index; NIL: near-isogenic line; RUE: radiation use efficiency; TDM: total above-ground dry matter; TRI: total solar radiation intercepted

SOWING DATE AND IRRIGATION EFFECTS ON PRODUCTIVITY AND WATER USE EFFICIENCY IN SUNFLOWER

Abiotic stresses represent a major impediment to crop productivity, especially in arid regions. Thus, over two years of 2014 and 2015, a field experiment was undertaken at El Nubaria region, Egypt to assess the productivity and water use efficiency (WUE) of sunflower as affected by planting dates (April 21, May 21, and June 21) and irrigation levels (ET100%, ET85% and ET70%,). Results clarified that leaf chlorophyll a content was higher by sowing in May than in either April or June sowings, while leaf carotenoides of plant sown in May or June surpassed those sown in April. The minimal value of proline was obtained with sowing in May. Sowing in May increased plant height by 52.2 and 22.3 as well as LAI by 19.3 and 73.1% than sowing in April and June, respectively. The reductions in seed yield, oil yield and WUE amounted to 10.5 and 12.8, 13.7 and 18.3 as well as 11.8 and 9.8 % with April and June sowings, respectively, compared to May sowing. ET100% showed superiority over than ET85% and ET70% in improving sunflower yields and its attributes, but WUE did not affect. Sunflower sown in May and irrigated with ET100% gave the maximum values of seed yield and its attributes and WUE surpassing other interaction treatments. In June, WUE value increased under severe water deficit i.e. ET70% comparing to moderately water–stressed (ET85%) or well–watered conditions (ET100%).

Weed Control Practices and Varying Sowing Dates Effects on Seed Production of Pearl Millet (<i>Pennisetum americanum</i> L.) under Semi-Arid Environment

Peral millet being drought tolerant has substantial potential to contribute in food security ensuring the food, fodder and nutritional value in different Asian and African countries. Susceptibility to abiotic and biotic factors and low productivity are the main reasons for decreasing productivity and area of millets. In this context, evaluation of the effect of weed control practices and varying sowing dates on grain yield of kharif season grown pearl millet (Pennisetum americanum L.) was demonstrated at post graduate agriculture research station, University of Agriculture, Faisalabad during 2015. Forage pearl millet was sown at three different sowing dates i.e. mid-June, end of June and mid-July and four weed control practices viz. weedy check (no weeding), twice hoeing at 15 and 30 days after sowing (DAS), weed control using herbicides i.e. application of Atrazine (Awax 38 SC) @ 330 g a.i. ha-1 at 15 DAS, and twice foliar applications of 10% Sorghum water extract (Sorgaab) (at 15 and 30 DAS). The experiment was laid out in randomized complete block design (RCBD) under split plot arrangement, comprising of three replications. The treatments with varying sowing dates were randomized in main plots and weed control practices were in subplots. Results showed that the highest plant height (279.51 cm), leaf area (2777.80 cm2), fresh weight of leaves per plant (155.57 g), maximum number of grains per head (3162.0) and grain yield (3419.7 kg·ha-1) were obtained in the treatment combination of 30th June sowing × twice weed hoeing (at 15 and 30 DAS) while, maximum 1000-grain weight (8.45 g) was observed in treatments where weeds were controlled by hoeing (at 15 and 30 DAS). Moreover, cultural weed control practices reduce significantly weed density, fresh and dry Wight of weeds. In sum, it is concluded that to reduce the weed-crop competition and to gain higher productivity of pearl millet, field should be weed free 20 - 45 days after sowing.

Thermal requirements, growth and yield of pigeonpea [Cajanus cajan (L.) Millsp.] genotypes under different agroclimatic zones of Punjab

A field experiment was carried out at four locations i.e. Ludhiana, Bathinda, Faridkot and Gurdaspur to study the influence of diverse environments on symbiotic traits, thermal requirements, growth in terms of plant height (cm) and yield (kg/ha) of pigeonpea [Cajanus cajan (L.) Millsp.] genotypes under different agroclimatic zones of Punjab. Results indicated that crop sown on 15 May recorded the higher grain yield than later sowing dates of 1 June and 15 June at all the locations; 15 May sowing provided 23.3, 22.1 and 46.7% higher grain yield over 1 May, 1 June and 15 June sowing, respectively. Early sown crop acquired higher agro-climatic indices than delayed sowings. The crop sown on 15 May provided the maximum gross returns, net returns and B:C ratio as evident from the additional income of Rs 13599, 13040 and 22865 Rs/ha over 1 May, 1 June and 15 June sowing, respectively. Among the genotypes, AL 201 at Ludhiana and Gurdaspur, AL 1578 at Bathinda and PAU 881 at Faridkot resulted in the highest grain yield and maximum returns. The genotype AL 201 took more days to 50% flowering and maturity at all the locations. It can be concluded that 15 May is the optimum sowing date and AL 201 and PAU 881 are the promising genotypes for providing high productivity of pigeonpea under different agroclimatic zones of Punjab.