Timely sown maize hybrids improve the post-anthesis dry matter accumulation, nutrient acquisition and crop productivity.

Delayed sowing of maize hybrids could exacerbate the capability of maximizing the yield potential through poor crop stand, root proliferation, nutrient uptake, and dry matter accumulation coupled with the inadequate partitioning of the assimilates. This study appraised the performance of five recent maize hybrids viz., PMH-1, PJHM-1, AH-4158, AH-4271, and AH-8181 under timely and late sown conditions of the irrigated semi-arid ecologies. Timely sowing had the grain and stover yields advantage of 16-19% and 12-25%, respectively over the late sown maize hybrids. The advanced hybrids AH-4271 and AH-4158 had higher grain yields than the others. During the post-anthesis period, a greater dry matter accumulation and contribution to the grain yield to the tune of 16% and 10.2%, respectively, was observed under timely sown conditions. Furthermore, the nutrient acquisition and use efficiencies also improved under the timely sown. The nutrient and dry matter remobilization varied among the hybrids with AH-4271 and PMH-1 registering greater values. The grain yield stability index (0.85) was highest with AH-4158 apart from the least yield reduction (15.2%) and stress susceptibility index (0.81), while the maximum geometric mean productivity was recorded with the AH-4271 (5.46 Mg ha-1). The hybrids AH-4271 and PJHM-1 exhibited improved root morphological traits, such as root length, biomass, root length density, root volume at the V5 stage (20 days after sowing, DAS) and 50% flowering (53 DAS). It is thus evident that the timely sowing and appropriate hybrids based on stress tolerance indices resulted in greater yields and better utilization of resources.

Scalable diversification options delivers sustainable and nutritious food in Indo-Gangetic plains.

Indo-Gangetic plains (IGP) of South Asia have supported bulk of human and bovine population in the region since ages, and a spectacular progress has been made in food production. However, malnutrition, diminishing total factor productivity, and natural resource degradation continue to plague this cereal-dominated region, which is also vulnerable to climate change. Addressing these challenges would require a transition towards diversifying cereal rotations with agroecological cropping systems. A study was, therefore, conducted at the experimental farm of ICAR-CSSRI, Karnal on crop diversification and sustainable intensification options using agro-ecological approaches such as Conservation Agriculture (CA) and diversified cropping systems to ensure food and nutritional security while sustaining the natural resources. On 2 years mean basis, CA-based cropping system management scenarios (mean of Sc2-Sc7) using diversified crop rotations; increased the system yield by 15.4%, net return by 28.7%, protein yield by 29.7%, while using 53.0% less irrigation water compared to conventional tillage (CT)-based rice-wheat system (Sc1). Maize-mustard-mungbean on permanent beds (PBs) (Sc4) recorded the highest productivity (+ 40.7%), profitability (+ 60.1%), and saved 81.8% irrigation water compared to Sc1 (11.8 Mg ha-1; 2190 USD ha-1; 2514 mm ha-1). Similarly, Sc5 (maize-wheat-mungbean on PBs) improved productivity (+ 32.2%), profitability (+ 57.4%) and saved irrigation water (75.5%) compared to Sc1. In terms of nutritional value, Sc5 was more balanced than other scenarios, and produced 43.8, 27.5 and 259.8% higher protein, carbohydrate and fat yields, respectively, compared to Sc1 (0.93, 8.55 and 0.14 Mg ha-1). Scenario 5 was able to meet the nutrient demand of 19, 23 and 32 additional persons ha-1 year-1 with respect to protein, carbohydrate and fat, respectively, compared to Sc1. The highest protein water productivity (~ 0.31 kg protein m-3 water) was recorded with CA-based soybean-wheat-mungbean (Sc6) system followed by maize-mustard-mungbean on PBs (Sc4) system (~ 0.29 kg protein m-3) and lowest under Sc1. Integration of short duration legume (mungbean) improved the system productivity by 17.2% and profitability by 32.1%, while triple gains in irrigation water productivity compared to CT-based systems. In western IGP, maize-wheat-mungbean on PBs was found most productive, profitable and nutritionally rich and efficient system compared to other systems. Therefore, diversification of water intensive cereal rotations with inclusion of legumes and CA-based management optimization can be potential option to ensure nutritious food for the dwelling communities and sustainability of natural resources in the region.

Conservation agriculture based integrated crop management sustains productivity and economic profitability along with soil properties of the maize-wheat rotation.

Field experiments were conducted to evaluate eight different integrated crop management (ICM) modules for 5 years in a maize-wheat rotation (MWR); wherein, ICM1&2-'business-as-usual' (conventional flatbed maize and wheat, ICM3&4-conventional raised bed (CTRB) maize and wheat without residues, ICM5&6-conservation agriculture (CA)-based zero-till (ZT) flatbed maize and wheat with the residues, and ICM7&8- CA-based ZT raised bed maize and wheat with the residues. Results indicated that the ICM7&8 produced significantly (p < 0.05) the highest maize grain yield (5 years av.) which was 7.8-21.3% greater than the ICM1-6. However, across years, the ICM5-8 gave a statistically similar wheat grain yield and was 8.4-11.5% greater than the ICM1-4. Similarly, the CA-based residue retained ICM5-8 modules had given 9.5-14.3% (5 years av.) greater system yields in terms of maize grain equivalents (MGEY) over the residue removed CT-based ICM1&4. System water productivity (SWP) was the highest with ICM5-8, being 10.3-17.8% higher than the ICM1-4. Nevertheless, the highest water use (TWU) was recorded in the CT flatbed (ICM1&2), ~ 7% more than the raised bed and ZT planted crops with or without the residues (ICM4-8). Furthermore, the ICM1-4 had produced 9.54% greater variable production costs compared to the ICM5-8, whereas, the ICM5-8 gave 24.3-27.4% additional returns than the ICM1-4. Also, different ICM modules caused significant (p < 0.05) impacts on the soil properties, such as organic carbon (SOC), microbial biomass carbon (SMBC), dehydrogenase (SDH), alkaline phosphatase (SAP), and urease (URE) activities. In 0.0-0.15 m soil profile, residue retained CA-based (ICM5-8) modules registered a 7.1-14.3% greater SOC and 10.2-17.3% SMBC than the ICM1-4. The sustainable yield index (SYI) of MWR was 13.4-18.6% greater under the ICM7&8 compared to the ICM1-4. Hence, this study concludes that the adoption of the CA-based residue retained ICMs in the MWR could sustain the crop yields, enhance farm profits, save water and improve soil properties of the north-western plans of India.

Long-term conservation agriculture and best nutrient management improves productivity and profitability coupled with soil properties of a maize-chickpea rotation.

Conservation agriculture (CA)-based practices have been promoted and recouped, as they hold the potential to enhance farm profits besides a consistent improvement in soil properties. A 7 years' field experiment consisting of three crop establishment practices viz., zero-till flatbed (ZTFB), permanent beds (PNB), conventional system (CT) along with the three-nutrient management; nutrient expert-based application (NE), recommended fertilization (RDF), and farmers' fertilizer practice (FFP), was carried out from 2013 to 2020. The CA-based practices (ZTFB/PNB) produced 13.9-17.6% greater maize grain-equivalent yield (MGEY) compared to the CT, while NE and RDF had 10.7-20% greater MGEY than the FFP. PNB and ZTFB gave 28.8% and 24% additional net returns than CT, while NE and RDF had 22.8% and 17.4% greater returns, respectively over FFP. PNB and ZTFB had 2.3-4.1% (0.0-0.20 m soil layers) lower bulk density than the CT. Furthermore, microbial biomass carbon (MBC) increased by 8-19% (0.0-0.50 m soil layers) in ZTFB/PNB over the CT, and by 7.6-11.0% in NE/RDF over FFP. Hence, CA-based crop establishment coupled with the NE or RDF could enhance the yields, farm profits, soil properties of the maize-chickpea rotation, thereby, could sustain production in the long run.