Pod Initiation Stage Research Articles

Foliar application of agrochemicals enhance growth, productivity, quality and biochemical traits of soybean

Flower drop, senescence of flowers and inadequate pod filling pose significant challenges in soybean cultivation as rapid nutrient extraction from leaves during the reproductive stage accelerates leaf aging. The present study assessed the effect of foliar application of agrochemicals on growth, productivity, quality and biochemical traits of soybean at two locations during kharif (rainy) season of 2021 and 2022. The experiment comprised of ten treatments of foliar application of agrochemicals [absolute control, water spray, potassium nitrate (KNO3) 1.5%, NPK (19:19:19) 1.5%, boron 0.3%, ammonium molybdate (AM) 0.5%, thiourea 750 parts per million (ppm), urea 2.0%, muriate of potash (MOP) 0.5% and salicylic acid (SA) 100 ppm] at flower and pod initiation stages along with the recommended dose of fertilizer (RDF) in a randomized complete block design replicated thrice. Results revealed that foliar application of boron 0.3%, urea 2.0% and MOP 0.5% at Ludhiana and MOP 0.5%, potassium nitrate 1.5% and urea 2.0% at Ballowal Saunkhri increased growth (plant height and dry matter accumulation), yield attributes (number of pods plant−1, number of filled pods plant−1 and 100-seed weight) and seed yield. These agrochemicals showed positive effects on the biochemical parameters with increased levels of proline and total phenol content as well as improvements in total soluble sugars, starch and protein content. The findings suggest that foliar application of agrochemicals (boron 0.3%, urea 2.0%, MOP 0.5% and potassium nitrate 1.5%) along with RDF can improve soybean growth and seed yield by mitigating the nutrient stress at reproductive stages.

Weather Parameter’s Impact on Natural Parasitization by Campoletis chlorideae Uchida in Chickpea Ecosystem - New Alluvial Zone of West Bengal

Background: A major biotic constraint in chickpea (Cicer arietinum L.) production is gram pod borer, Helicoverpa armigera (Hübner). However, the population of this pest is reduced to some extent by a solitary endo-larval parasitoid, Campoletis chlorideae Uchida under field conditions. Climate change has a greater impact on natural enemies’ effectiveness used in field-level pest management. Therefore, the present study was conducted to understand the impact of weather factors on C. chlorideae parasitization rate of H. armigera in chickpea grown in the new alluvial agro-climatic zone of West Bengal. Methods: Chickpea was grown in a randomized complete block design (RCBD) with three replications during Rabi 2017-18, 2018-19 and 2019-2020, at Mondouri farm, Bidhan Chandra Krishi Visawavidayala, Mohanpur, West Bengal. To know the most significant weather parameter which influences C. chlorideae parasitization or parasitoid incidence, H. armigera larvae (2nd instar) collected from the field experiment were reared until cocoon formation and parasitization % was correlated with weather parameters and subsequently subjected to stepwise regression analysis. Result: The larval endo-parasitoid, C. chlorideae marked its first appearance from 3rd SMW after the appearance of H. armigera and its activity was high (68% to 72% parasitization) during the flowering to pod initiation stage and thereafter declined gradually. Among the weather variables, only temperature (maximum and minimum) had a consistent and significant negative correlation with C. chlorideae incidence and was responsible for nearly 50% C. chlorideae incidence. An increase in 1°C temperature results in a decrease of 4% parasitoid incidence. Thus, climate change in the near future will have a considerable influence on the overall survival, development and rate of parasitization of parasitoids.

Performance of Summer Greengram (Vigna radiate L.) under Various Orientations in Semi-arid Region, Haryana (India)

Background: Summer green gram (Vigna radiata L.) commonly known as “moong” belongs to the Fabaceae family that currently is grown in different parts of the world and it has a significant role in nutrition in developing countries. It is a short-duration crop grown over a wide range of environments in India. Light interception and penetration as well as albedo are affected by row orientation. Methods: Line Quantum sensor (Model L1-191R) was used to measure PAR (400 nm-700 nm) at important phenophases at different orientations. In order to better understand how plants absorb light in different row orientations, such as North-South (NS), East-West (EW) and North-West-Southeast (NW-SE), a study was carried out at the Chaudhary Charan Singh Research Farm of Agricultural Meteorology at the Haryana Agricultural University in Hisar India during summer 2020 and 2021. Heat and radiation use efficiency measure at flowering, pod and physiological maturity by using weather data and other indices. Result: It was found that moong variety MH 421’s pod initiation stage was when PAR absorption was greatest, along with other factors including NW-SE orientation. Row orientation heat use efficiency ranges between (2.6 to 7.6 kg ha-1 °C day-1) and in variety (1.4 to 2.7 g MJ-1) and radiation use efficiency ranges between (1.4 to 2.8 g MJ-1) and in row orientation (1.4 to 2.7 g MJ-1) (2.7 to 7.7 kg ha-1 °C day-1). As a consequence, it was determined that diagonal row orientations generated better yield and yield attributes because PAR absorption was higher in such orientations. In dry and semi-arid areas, it can be used to produce food and forage.

Effect of Foliar Application of Nutrients on Growth and Yield Attributes of Blackgram (Vigna mungo L.) under Rainfed Condition of Southern Rajasthan

A field experiment was conducted at Dryland Farming Research Station, Arjia, Bhilwara, MPUAT, Udaipur during kharif, 2022 to assess the effect of foliar application of nutrients on growth and yield attributes of black gram (Vigna mungo L.) under rainfed condition of southern Rajasthan. The experiment consisted of eight treatments and replicated thrice in Randomized Block Design (RBD). The foliar spray of nutrients was done at flower and pod initiation stage. The experiment results revealed that maximum plant height (cm) (63.18), dry matter accumulation plant-1 (9.15), number of nodules plant-1 (48.02) and weight of nodules plant-1 were registered with treatment T8 (RDF + Foliar spray of NPK (18:18:18) @ 2% + ZnSO4 @ 0.5%). Significantly higher number of pod plant-1 (37.15), pod length (5.10 cm), number of seed pod-1 (7.42), test weight (43.94 g), grain yield (950 kg ha-1) and straw yield (1808.33 kg ha-1) were also reported in the same treatment of RDF + Foliar spray of NPK (18:18:18) @ 2% + ZnSO4 @ 0.5% (T8 ) and it was at par with treatment T7 (RDF + Foliar spray of DAP @ 2% + ZnSO4 @ 0.5%).

Influence of Foliar Application of Nutrients on Yield and Yield Attributes of Black Gram (Vigna mungo L.)

The present experiment was laid out at research farm of R.A.K. College of Agriculture, Sehore (M.P.) during Kharif season of 2022. The experiment was laid out in a randomized complete block design with 8 treatments and each treatment replicated three times. The Blackgram (cv. Pratap -1) was sowing with a seed rate of 15 kg ha-1 and with a spacing of 30 cm x 10 cm. The recommended dose of chemical fertilizer viz. 20:40:20 kg ha-1 N: P2O5: K2O, respectively was applied to the crop. Results revealed that foliar spray application of nutrient shows significant effect on yield and yield attributes. Treatment T7 (2% Spray of DAP + 0.5% Spray of ZnSO4 at pre-flowering and pod initiation stage) found higher for yield and yield attributes i.e. number of pods/plant (13.67), number of seeds/pods (6.15), seed index (4.76 g), seed yield/plant (2.21 g), seed yield/plot (836 g), seed yield/ha (786 kg), straw yield (1730 kg/ha), biological yield (2516 kg/ha), harvest index (31.21 %). While, minimum values found with T1 (Water spray at pre-flowering stage and pod initiation stage).

Impact of Foliar Application of Nutrients on Economics of Black Gram (Vigna mungo L.)

The present experiment was laid out at research farm of R.A.K. College of Agriculture, Sehore (M.P.) during Kharif season of 2022. The experiment was laid out in a randomized complete block design with 8 treatments and each treatment replicated three times. The Blackgram (cv. Pratap -1) was sowing with a seed rate of 15 kg ha-1 and with a spacing of 30 cm x 10 cm. The recommended dose of chemical fertilizer viz. 20:40:20 kg ha-1 N: P2O5: K2O, respectively was applied to the crop. Results revealed that foliar spray application of nutrient shows significant effect on yield economics. Treatment T7 (2% Spray of DAP + 0.5% Spray of ZnSO4 at pre-flowering and pod initiation stage) found higher for yield and yield attributes i.e. grain yield (0.836 kg/plot and 7.86 q/ha respectively), straw yield (17.30q/ha), biological yield (25.16 q/ha), harvest index (31.21 %), gross return (₹ 62550 ha-1), net return ((₹ 36491 ha-1) and B:C ratio (2.40). While, minimum values found with T1 (Water spray at pre-flowering stage and pod initiation stage).

Effect of Foliar Application of Different Chemicals on Yield and Yield Attributes of Black gram [Vigna mungo (L.) Hepper] under Rainfed Condition

A field experiment was performed at the “TCA., research farm of Dholi (Muzaffarpur), which is a unit of the Dr. Rajendra Prasad Central Agricultural University, Pusa (Samastipur), Bihar, during the Kharif season of 2021” to investigate the “Effect of foliar application of different chemicals on yield attributes and yield of Black gram [Vigna mungo (L.) Hepper] under rainfed condition”. The design used for making layout of experimental unit was RBD, that was replicated three times, with ten treatments in each replication for a total of 30 plots. The experiment conducted with 10 treatments viz., Absolute Control (T1), Water Spray (T2), ZnSO4 @ 0.5% Spray (T3), NPK (19-19-19) @ 2% Spray (T4), Urea @ 2% Spray (T5), DAP @ 2% Spray (T6), Salicylic acid @ 100 ppm Spray (T7), Potassium Nitrate @ 2% Spray (T8), Boron 0.25 % Spray (T9), Potassium Chloride @ 0.2% Spray(T10). The foliar spray of different treatments applied had a significant impact on the number of pod number plant-1, seed count pod-1 and the length of the pod. However, foliar chemicals had no appreciable impact on the weight of 100 seeds. At pre-flowering and pod-initiation stage, foliar treatment of “NPK (19-19-19) @ 2 % spray (T4)” resulted in significantly greater seed production and stover output. Different chemical administration to the foliage had no significant effect on harvest index.

Effect of fertility levels and foliar nutrition in fieldpea (Pisum sativum) under south - eastern Rajasthan

An experiment was conducted during the winter (rabi) season of 2016–17, 2017–18 and 2018–19 at the Agriculture University, Kota, Rajasthan, to evaluate the effect of fertility levels and foliar nutrition on fieldpea (Pisum sativum L.). The experiment consisted of 3 recommended dose of fertilizers (RDF) levels (75%, 100% and 125%) and 5 foliar sprays [water spray, neem-coated urea 2%, NPK (19 : 19 : 19) 0.5%, NPK (17 : 44 : 0) 0.5% and NPK (0 : 0 : 50) 0.5%] at pre-flowering and pod-initiation stages. Result revealed, that the maximum and significantly higher plant height (168.21 cm), branches/plant (3.12), nodule count (23.75), nodule dry weight (35.87 g/plant), pods/plant (61.90), seeds/pod (3.78), grain yield (2350 kg/ha), net returns (`52,889/ha) and benefit : cost ratio (3.02) were recorded with application of 125% RDF (25 kg N + 50 kg P + 25 kg K + 25 kg S + 6.25 kg Zn/ha) with 7.32, 10.64, 13.54, 11.40, 15.81, 12,17, 26.82, 32.18 and 16.60% increase over 75% RDF. Application of 125% RDF recorded the maximum nutrient content (N : P : K : S 3.30 : 0.54 : 1.18 : 0.40% in seed and 1.69 : 0.48 : 1.51 : 0.31% in straw) and uptake (N : P : K : S 77.57 : 12.59 : 27.68 : 9.42 kg/ha in seed and 58.14 : 16.35 : 51.99 : 10.67 kg/ha in straw) over the other treatments. Among foliar applications, NPK (19 : 19 : 19) @ 0.5% at pre-flowering and pod- initiation stage resulted in the maximum and significantly higher plant height (167.76 cm), branches/plant (3.14), nodule count (23.77), nodule dry weight (36.36 g/plant), pods/plant (63.43), seeds/pod (3.89), grain yield (2,250 kg/ha), net returns (`50,835/ha) and benefit: cost ratio (3.06) over rest of treatments with 9.69, 12.95, 8.69, 10.06, 23.38, 18.24, 12.84, 17.19 and 15.47% increase over the control; however, it recorded at par results with NPK (17 : 44 : 0) @ 0.5% at pre-flowering and pod-initiation stage. Similarly, higher NKS uptake in seed and straw was observed under foliar application of NPK (19 : 19 : 19) @ 0.5% and P uptake under NPK (17 : 44 : 0) @ 0.5% than the other treatments.

Effect of Liquid Organic Foliar Spray on Chickpea (Cicer arietinum L.) under Rainfed Condition

Aims: Foliar nutrition is aimed to eliminate the problems of fixation and immobilization of nutrients. Hence, foliar nutrition is being recognized as a significant way of fertilizing modern agriculture, especially under rainfed conditions. Liquid organic manures are the concoctions of micro and macronutrients that also contain vitamins, amino acids, growth-promoting substances, and beneficial microbes.
 Study Design: The experiment was laid out in a split plot design with three replications.
 Place and Duration of Study: A field experiment was conducted in medium black soils at Regional Agricultural Research Station, Vijayapur, during Rabi, 2020-21.
 Methodology: There were fifteen treatment combinations, consisting of five organic sources (vermiwash @ 10%, cowurine @ 10%, jeevamrutha @ 25%, bio digester filtrate @ 25% and urea @ 2%) in main plots and three stage of application (pre flowering, pod initiation and pre flowering + pod initiation) in sub plots for JG-11 variety of chickpea.
 Results: Foliar application of jeevamrutha @ 25% both at pre flowering and at pod initiation stages recorded significantly greater dry matter accumulation in leaves, stem and reproductive parts, higher SPAD values, number of pods plant-1 (46.5), grain weight plant-1 (9.45 g), harvest index (2198 kg ha-1). Soil dehydrogenase activity, protein content and protein yield parameters also showed higher values for the same treatment along with the major nutrient uptake. A significant reduction in the observation of pest load of chickpeas at pod development stage was noticed by the application of treatment.
 Conclusion: Foliar application of liquid organic manures, either jeevamrutha @ 25% or cow urine @ 10% both at pre-flowering and at pod initiation stages helped to increase growth, growth attributes like dry matter accumulation, SPAD values, yield attributes, protein content, dehydrogenase activity, major nutrient uptake and reduction of pest load in chickpea.

Response of N P S doses and urea foliar spray on lentil under guava (Psidium guajava) + lentil (Lens culinaris) based agri-horti system

An experiment was conducted at research farm of Rajiv Gandhi South Campus, Barkachha, Mirzapur situated in eastern Uttar Pradesh during winter (rabi) season of 2021–22 with the objective to study the response of nitrogen, phosphorous, sulphur doses and urea foliar spray on lentil growth attributes, yield attributes, yield and economics under guava + lentil based agri-horti system. Results revealed that the higher growth, yield attributes, yield, net monetory returns and benefit-cost ratio were recorded under N23.5+P60+S40 which was at par with N20+P50+S30. In case of varied doses of foliar spray of urea, foliar spray of 2% urea at pre-flowering stage fb 2% urea at pod initiation stage recorded significantly higher growth, yield, yield attributes and economics which was at par with foliar spray of 2% urea spray at pre-flowering stage. Moreover, between the sowing of the lentils and the harvest, the guava's growth attributes were also increased. Therefore, under rainfed conditions of Vidhyan region of eastern Uttar Pradesh, application of nitrogen, phosphorus and sulphur @20, 50 and 30 kg/ha as basal application along with foliar application (spray) of 2% urea at pre-flowering stage (45 DAS) to lentil crop was found to be better option for higher profitability under guava plantation.

Accumulation of phytochemicals at different growth stages of Cleome gynandra grown under greenhouse and microplot conditions ​

Phytochemicals are bioactive non-nutrient plant compounds that accumulate in response to environmental changes and possess medicinal properties. The concentration of these useful phytochemicals is well associated with the stage of the crop and also the management practices adopted. Therefore, a greenhouse and open field microplot experiments were conducted to investigate the accumulation of phytochemicals at different growth stages of Cleome gynandra. Seven treatments constituting fifth leaf stage (control), vegetative, flower-bud, flowering, pod initiation, pod filling and physiological maturity stages were arranged in RCBD, with 10 replications. Young leaves and tender shoots were harvested weekly and then subjected to phytochemical analysis. Data on antioxidant activity (AA), total phenolics (TP), total flavonoids (TF) and proanthocyanidins (PAs) were determined prior to analysis of variance through SAS Software. Under greenhouse conditions, relative to the control, accumulation of AA and PAs was the highest (66.84 mg GAE/g and 18.62% DM) at flower-budding stage, whereas the lowest (39.63 mg GAE/g and 2.26% DM) was observed at pod initiation stage, respectively. No significant (P 0.05) effect on TP and TF contents were observed. Under microplot conditions, the highest (58.02 mg GAE/g) AA was observed during flower-budding stage and the lowest ( 30.14 mg GAE/g) was observed at physiological maturity. In contrast, the accumulation of TP and TF was the highest (20.23 mg GAE/g and 8.11 mg QE/g) during flower-budding stage, whereas the lowest (3.18 mg GAE/g and 0.93 mg QE/g) was observed at pod initiation stage. However, no significant (P 0.05) effect was observed on PAs. In conclusion, the phytochemicals evaluated in C. gynandra similarly had the highest accumulation at the flower budding stage under greenhouse and open field microplot conditions, however, they started declining at pod initiation stage towards physiological maturity.

Accumulation of phytochemicals at different growth stages of Cleome gynandra grown under greenhouse and microplot conditions ​

Phytochemicals are bioactive non-nutrient plant compounds that accumulate in response to environmental changes and possess medicinal properties. The concentration of these useful phytochemicals is well associated with the stage of the crop and also the management practices adopted. Therefore, a greenhouse and open field microplot experiments were conducted to investigate the accumulation of phytochemicals at different growth stages of Cleome gynandra. Seven treatments constituting fifth leaf stage (control), vegetative, flower-bud, flowering, pod initiation, pod filling and physiological maturity stages were arranged in RCBD, with 10 replications. Young leaves and tender shoots were harvested weekly and then subjected to phytochemical analysis. Data on antioxidant activity (AA), total phenolics (TP), total flavonoids (TF) and proanthocyanidins (PAs) were determined prior to analysis of variance through SAS Software. Under greenhouse conditions, relative to the control, accumulation of AA and PAs was the highest (66.84 mg GAE/g and 18.62% DM) at flower-budding stage, whereas the lowest (39.63 mg GAE/g and 2.26% DM) was observed at pod initiation stage, respectively. No significant (P 0.05) effect on TP and TF contents were observed. Under microplot conditions, the highest (58.02 mg GAE/g) AA was observed during flower-budding stage and the lowest ( 30.14 mg GAE/g) was observed at physiological maturity. In contrast, the accumulation of TP and TF was the highest (20.23 mg GAE/g and 8.11 mg QE/g) during flower-budding stage, whereas the lowest (3.18 mg GAE/g and 0.93 mg QE/g) was observed at pod initiation stage. However, no significant (P 0.05) effect was observed on PAs. In conclusion, the phytochemicals evaluated in C. gynandra similarly had the highest accumulation at the flower budding stage under greenhouse and open field microplot conditions, however, they started declining at pod initiation stage towards physiological maturity.

Positioning New Pesticide Chemistries in the Management of Pod Fly, Melanagromyza obtusa Malloch (Diptera: Agromyzidae) in Pigeonpea

Background: Pigeonpea is an important pulse-cum-grain legume crop of India. Major constraint in its production is the insects damage. Pod fly, Melanagromyza obtusa is of regular occurrence in South and Central India causing yield loss to the tune of 60 to 80 per cent particularly in late maturing pigeonpea crop. Due to its feeding habit as an internal borer, cultural, biological and mechanical methods are ineffective in reducing the damage due to pod fly and insecticides play a paramount role in managing their population under field conditions. Hence, present study have been aimed to evaluate the efficacy of different new pesticide chemistries against pod fly in pigeon pea ecosystem. Method: Two field experiments were conducted during Kharif 2019 and 2020 in RCBD using pigeonpea cv. GRG 811 with 14 treatments replicated twice. Two sprays were imposed at 15 days interval initiating from pod initiation stage. At maturity, number of damaged pods were recorded and expressed as percentage. Grain yield was recorded and benefit cost ratio was also worked out. Results: Among the screened insecticides, fipronil 4+thiamethoxam 4 SC @ 40+40 g a.i./ha followed by thiamethoxam 25 WG @ 50 g a.i./ha and fipronil 40+imidacloprid 40 WG @ 160+160 g a.i./ha provided better control of pod fly in terms of reduction in pod damage (69.54, 62.13 and 62.57%) and seed damage (72.51, 71.35 and 70.39%) respectively over untreated check. The average grain yield of 1577 kg/ha was highest in fipronil 4+thiamethoxam 4 SC @ 40+40 g a.i./ha followed by fipronil 40+imidacloprid 40 WG @ 160+160 g a.i./ha (1555.5 kg/ha) and thiamethoxam 25 WG @ 50 g a.i./ha (1536.5 kg/ha). Whereas, B: C was higher in fipronil 4+thiamethoxam 4 SC @ 40+40 g a.i./ha (2.84) and thiamethoxam 25 WG @ 50 g a.i./ha (2.83). Therefore these insecticides can be used for effective management of pod fly.

Foliar Application of Macro- and Micronutrients Improves the Productivity, Economic Returns, and Resource-Use Efficiency of Soybean in a Semiarid Climate

Inadequate nutrient management is one of the major challenges for sustainable soybean production in semi-arid climatic conditions. Hence, a 3-year (2015–2017) field experiment was conducted to assess the effect of foliar application of macro- and micronutrients on the growth, productivity, and profitability of soybean. Eight foliar nutrient sprays at the pod initiation stage—water spray (WS), 2% urea solution, 2% di-ammonium phosphate solution (DAP2%), 0.5% muriate of potash solution (MOP0.5%), 2% solution of 19:19:19 nitrogen phosphorus and potassium (NPK2%), and a 0.5% solution each of molybdenum (Mo0.5%), boron (B0.5%), chelated-zinc (Zn 0.5%) and no-foliar nutrition (NFN)—were compared with a basal-applied recommended dose of fertilizers (RDF: 30 kg N, 75 kg P, and 40 kg K ha−1) in a randomized block design (RBD), replicated three times. Foliar-applied chelated Zn@0.5% (Zn0.5%) at the pod initiation stage resulted in more pods per plants. In addition to Zn0.5%, urea2%, NPK2%, and B0.5% significantly improved the pods per plant over treatment by no-foliar nutrition (NFN). The RDF-supplied soybean subsequently sprayed with Zn0.5% produced the highest seed yield, which was 18.5–37.8% higher than that of NFN treatment Yield improvement due to the application of B0.5%, DAP2%, and urea2% varied between 19.2–23.7, 16.6–20.4 and 18.6–20%, respectively. Foliar nutrition showed the largest net returns from Zn0.5%. The water-use efficiency (WUE) and production efficiency increased by 18.4–37.6 and 34.9–37.5%, respectively, due to Zn0.5% over the efficiencies from NFN treatment. Monetary efficiency (ME) gains due to Zn0.5% were 24% higher, while ME efficiency gains due to urea2%, NPK2%, and B0.5% varied between 15–16%. Thus, this study suggested that the foliar application of 0.5% Zn and B, urea, NPK fertilizer, and DAP at 2%, along with RDF. is a profitable nutrient management option for quality soybean production in a semiarid region. However, nutrient partitioning, changes in soil chemical and biological indicators, and environmental aspects need critical examination in future studies.

Foliar Nutrition of Zinc and Iron on Quality and Productivity of Summer Mungbean (Vigna radiata L.)

A field experiment was carried out at RRTTSS, Kirei, Sundargarh during summer season 2021 to find out the effect of foliar nutrition of zinc and iron on quality and productivity of summer mungbean (Vigna radiata L.). The results revealed that seed yield (521 kg ha-1), stover yield (1307 kg ha-1), gross returns (¹ 36470 ha-1), net returns (¹ 8020 ha-1) and benefit: cost ratio (1.28) as well as nutrient content in seed (3.86, 0.45 and 0.65% NPK) and in stover (1.25, 0.19 and 1.88% NPK) were recorded significantly highest values under the T6 treatment [0.5% ZnSO4 and 0.5% FeSO4 foliar spray at flower initiation (FI) stage along with recommended dose of fertilizer (RDF) and FYM]. The highest Zn content in seed (51.01 ppm) and stover (17.43 ppm) was obtained in T3 treatment [T1 + 0.5% ZnSO4 at flower initiation (FI) and pod initiation (PI) stage]. However, the maximum iron content in seed (117.50 ppm) as well as in stover (84.97 ppm) was recorded in T5 treatment (T1 + 0.5% FeSO4 at FI and PI stage).

Correlation of stress indices with yield parameters in wild chickpea (Cicer arietinum L.) accessions under irrigated and rainfed conditions

Six wild chickpea accessions were procured during Rabi seasons 2015-16 and 2016-17 seasons at Punjab Agricultural University, Ludhiana to record morpho-physiological parameters and yield components at pod initiation stage. The experiment was carried out in randomized block design with two treatments irrigated and rainfed each with three replicates. Results indicated a significant decrease in the specific leaf weight (SLW), photosynthetic rate (PR) and relative water content (RWC) under rainfed conditions in wild chickpea accessions. Wild accessions C judaicum 17148 (29.5%) and C pinnatifidum212 (31.0%)displayed their resistance towards water scarcity by maintaining high relative water content that depicted negative correlation with membrane damage (r=-0.98).The membrane damage showed an inversely proportional relationship (r=-0.69) with seed weight, a yield component under rainfed conditions evidencing the requirement of water at pod filling stage.

Growth Rate, Dry Matter Accumulation, and Partitioning in Soybean (Glycine max L.) in Response to Defoliation under High-Rainfall Conditions.

The frequency of heavy rains is increasing with climate change in regions that already have high annual rainfall (i.e., Sichuan, China). Crop response under such high-rainfall conditions is to increase dry matter investment in vegetative parts rather than reproductive parts. In the case of soybean, leaf redundancy prevails, which reduces the light transmittance and seed yield. However, moderate defoliation of soybean canopy could reduce leaf redundancy and improve soybean yield, especially under high-rainfall conditions. Therefore, the effects of three defoliation treatments (T1, 15%; T2, 30%; and T3, 45% defoliation from the top of the soybean canopy; defoliation treatments were applied at the pod initiation stage of soybean) on the growth and yield parameters of soybean were evaluated through field experiments in the summer of 2017, 2018, and 2019. All results were compared with nondefoliated soybean plants (CK) under high-rainfall conditions. Compared with CK, treatment T1 significantly (p < 0. 05) improved the light transmittance and photosynthetic rate of soybean. Consequently, the leaf greenness was enhanced by 22%, which delayed the leaf senescence by 13% at physiological maturity. Besides, compared to CK, soybean plants achieved the highest values of crop growth rate in T1, which increased the total dry matter accumulation (by 6%) and its translocation to vegetative parts (by 4%) and reproductive parts (by 8%) at physiological maturity. This improved soybean growth and dry matter partitioning to reproductive parts in T1 enhanced the pod number (by 23%, from 823.8 m−2 in CK to 1012.7 m−2 in T1) and seed number (by 11%, from 1181.4 m−2 in CK to 1311.7 m−2 in T1), whereas the heavy defoliation treatments considerably decreased all measured growth and yield parameters. On average, treatment T1 increased soybean seed yield by 9% (from 2120.2 kg ha−1 in CK to 2318.2 kg ha−1 in T1), while T2 and T3 decreased soybean seed yield by 19% and 33%, respectively, compared to CK. Overall, these findings indicate that the optimum defoliation, i.e., T1 (15% defoliation), can decrease leaf redundancy and increase seed yield by reducing the adverse effects of mutual shading and increasing the dry matter translocation to reproductive parts than vegetative parts in soybean, especially under high-rainfall conditions. Future studies are needed to understand the internal signaling and the molecular mechanism controlling and regulating dry matter production and partitioning in soybean, especially from the pod initiation stage to the physiological maturity stage.

Alleviation of Sodicity Stress in Green Gram and Black Gram Using Plant Growth Regulating Substances

Most of the pulses in India are grown in low fertility, problematic soils and unpredictable environmental conditions. Major issues in pulse production are poor establishment and low harvest index. In pulses harvest index is only 15-20%. Physiological manipulations such as spraying of hormones and nutrients that reduce flower drop and thereby facilitate large sink size. The objective of this research is to study the impact of Growth regulating substances on germination and establishment and economic yield of black gram and green gram under Sodic soil conditions. The study area is Anbil Dharmalingam Agricultural College and Research Institute, Trichy. The nature of soil is sodicity with exchangeable sodium percentage (ESP) of 18.94% with pH of 9.02. The two crop varieties green gram VBN (Gg) 2 &amp; black gram VBN (Bg) 6 were employed under sodic soil condition. Field experiment was conducted during late July to October 2017 under sodic soil condition with ten treatments. The experiment was laid out in a Randamized Block Design with three replications. Foliar spray was given at flower initiation and pod initiation stages. Ten treatment combinations were employed by T1: Control, T2: Seed Treatment (ST) with Ammonium Molybdate (AM) 0.05% + foliar spray of ZnSO4 – 0.5%. T3: AM 0.05% + Panchagavya -3.0%, T4: AM 0.05% + foliar spray of KCl -1%, T5: ST with GA3 50 ppm + foliar spray of ZnSO4 – 0.5%, T6: GA3 50 ppm + Panchagavya -3.0%, T7: GA3 50 ppm + KCl -1%, T8: Cowpea Sprout Extract 2% +ZnSO4 – 0.5%, T9: Cowpea Sprout Extract 2% +Panchagavya -3.0%, T10: Cowpea Sprout Extract 2% + foliar spray of KCl -1%. In conclusion the yield enhancement in best treatment may be due to the presence of bioactive substances in sprouted cowpea extracts and panchagavya were found effective towards yield maximization.

Towards withholding irrigation regimes and drought-resistant genotypes as strategies to increase canola production in drought-prone environments: A modeling approach

The current study evaluated the development and growth of three major rapeseed genotypes (Hyola308, Hyola401, and RGS003 as early-, mid-, and late-maturity genotypes, respectively) as well as seed yield under different irrigation regimes (full irrigation, withholding irrigation at the flowering stage, withholding irrigation at the pod initiation stage, and withholding irrigation at the seed filling period) and also the spatial yield potential. APSIM-Canola model was applied to investigate the response of rapeseed genotypes to irrigation regimes in ten locations. Simulated results indicated that yield potential for rapeseed production was higher in the west which is a temperate agro-climatic zone (2852.6 kg ha−1) than in the southwest which is a hot agro-climatic zone (1885.1 kg ha−1). Although Hyola401 (the mid-maturity genotype) had the maximum seed yield (2798.4 kg ha−1), RGS003 (the late-maturity genotype) was found to be more drought-resistant due to a lower decrease in seed yield (18.1 %) under water-limited conditions compared with full irrigation conditions. The current findings suggest that the mid-maturity genotype has more yield potential in the studied locations (with different climates and soils) under full irrigation conditions due to higher seed yield, and the late-maturity genotype can be suggested as a resistant genotype for future breeding programs to introduce new-high-yielding genotypes with high drought tolerance, especially in drought-prone environments. Furthermore, withholding irrigation at seed filling onwards, which showed the lowest decrease in seed yield (13.6 %), can be recommended as a strategy for water-saving at the end of the growing season, and farmers can allocate irrigation water to other crops.

Management of Pod fly, Melanagromyza obtusa on Pigeonpea (Cajanus cajan L.)

Background: Pod fly, Melanagromyza obtusa is one of the most obnoxious pest causing grain damage ranging from 10-80% with a monitory loss of US$ 256 million annually. Being an internal feeder, infested pods do not show any external symptoms of damage until the fully grown maggots chew the pod wall, leaving a thin papery membrane intact called as window, through which adults exit from the pod. Several field studies were conducted to determine the efficacy of insecticides for the control of pod fly. However, these findings did not find acceptability and led to partial success. Insecticides that should leave lesser residues and pose lesser environmental threat have become imperative. The present study aimed to evaluate the efficacy of certain new insecticide molecules against pod fly in pigeonpea ecosystem. Methods: Two field experiments were conducted at Regional Agricultural Research Station, Lam, Guntur during Kharif, 2012 and 2013 in a randomized block design (RBD) using pigeonpea cv. ICPL 85063 (Lakshmi) with 17 treatments including untreated control and 3 replications. Two sprays were given at 10 days interval starting from pod initiation stage. At maturity, number of pods showing pod fly damage were recorded and expressed as percentage. Grain yield was recorded and cost–benefit ratio was worked out. Result: Among different insecticides, thiacloprid 21.7 SC, followed by diafenthiuron 50 WP, flubendiamide 480 SC and dimethoate 30 EC were very effective against pod fly with more grain yield and registered highest incremental cost benefit ratio (ICBR). It was further suggested that effective insecticides may be alternated in order to avoid development of resistance to pod fly in pigeonpea.