Contribution of water and radiation to growth and yield of pearl millet in Deccan plateau - A case study

In this study the agrometeorological data for the period from 1991 to 1997 have been used to study evapotranspiration demand and crop characteristics of pearl millet at Solapur. Crop coefficients, water use efficiency and radiation use efficiency have been worked out and discussed. This has been done for two varieties of the crop viz., ICTP-8203 and Shraddha. The study revealed that pearl millet crop consumed maximum amount of water during earhead emergence phase, followed by flowering phase. During earhead emergence and flowering phase together, ICTP-8203 variety used nearly 50% of total water used while shraddha consumed about 60%. The highest values of crop coefficient are seen during earhead emergence phase for both the varieties. Maximum photosynthetically active radiation is availed by the crop during its vegetative phase. Radiation use efficiency is more for ICTP-8203 variety than Shraddha variety.

Cultivated and wild pearl millet display contrasting patterns of abundance and co-occurrence in their root mycobiome

Fungal communities associated with roots play a key role in nutrient uptake and in mitigating the abiotic and biotic stress of their host. In this study, we characterized the roots mycobiome of wild and cultivated pearl millet [Pennisetum glaucum (L.) R. Br., synonym: Cenchrus americanus (L.) Morrone] in three agro-ecological areas of Senegal following a rainfall gradient. We hypothesized that wild pearl millet could serve as a reservoir of endophytes for cultivated pearl millet. We therefore analyzed the soil factors influencing fungal community structure and whether cultivated and wild millet shared the same fungal communities. The fungal communities associated with pearl millet were significantly structured according to sites and plant type (wild vs cultivated). Besides, soil pH and phosphorus were the main factors influencing the fungal community structure. We observed a higher fungal diversity in cultivated compared to wild pearl millet. Interestingly, we detected higher relative abundance of putative pathotrophs, especially plant pathogen, in cultivated than in wild millet in semi-arid and semi-humid zones, and higher relative abundance of saprotrophs in wild millet in arid and semi-humid zones. A network analysis based on taxa co-occurrence patterns in the core mycobiome revealed that cultivated millet and wild relatives had dissimilar groups of hub taxa. The identification of the core mycobiome and hub taxa of cultivated and wild pearl millet could be an important step in developing microbiome engineering approaches for more sustainable management practices in pearl millet agroecosystems.

Stage specific comparative transcriptomic analysis to reveal gene networks regulating iron and zinc content in pearl millet [Pennisetum glaucum (L.) R. Br.]

Pearl millet is an important staple food crop of poor people and excels all other cereals due to its unique features of resilience to adverse climatic conditions. It is rich in micronutrients like iron and zinc and amenable for focused breeding for these micronutrients along with high yield. Hence, this is a key to alleviate malnutrition and ensure nutritional security. This study was conducted to identify and validate candidate genes governing grain iron and zinc content enabling the desired modifications in the genotypes. Transcriptome sequencing using ION S5 Next Generation Sequencer generated 43.5 million sequence reads resulting in 83,721 transcripts with N50 of 597 bp and 84.35% of transcripts matched with the pearl millet genome assembly. The genotypes having high iron and zinc showed differential gene expression during different stages. Of which, 155 were up-regulated and 251 were down-regulated while during flowering stage and milking stage 349 and 378 transcripts were differentially expressed, respectively. Gene annotation and GO term showed the presence of transcripts involved in metabolic activities associated with uptake and transport of iron and zinc. Information generated will help in gaining insights into iron and zinc metabolism and develop genotypes with high yield, grain iron and zinc content.

Zero Tillage, Residue Retention and System-Intensification with Legumes for Enhanced Pearl Millet Productivity and Mineral Biofortification

Pearl millet-based cropping systems with intensive tillage operations prior to sowing have limited sustainable productivity in the low-irrigation conditions of semi-arid farming ecologies, such as those in the north Indian plains. The adoption of improved management practices such as zero tillage with residue retention (ZTR) and diversification with the inclusion of summer pulse crops has the potential to improve cropping system sustainability. Therefore, an experiment was designed to compare two improved management practices, zero tillage (ZT) and ZTR, to conventional tillage (CT), across three pearl millet-based cropping systems: pearl millet–chickpea (PM–CP), PM–CP–mungbean (MB), and PM–CP–forage pearl millet in a two-year experiment. Experimental treatments were compared in terms of pearl millet productivity, mineral biofortification, and greenhouse gas emissions. Results showed a significant increase in pearl millet yield attributes, grain and stover productivity, nutrient uptake, and micronutrient biofortification in the PM–CP–MB cropping system under ZTR relative to other treatment combinations. On-farm evaluation at different locations also showed that the intensification of PM–CP system using summer crops enhanced pearl millet productivity across diverse tillage systems. Overall, zero tillage practices combined with diversified pearl millet-based cropping systems are likely to be management practices, which farmers can use to sustainably maintain or increase cropping system productivity in the various semi-arid areas of the world.

Observations on the foraging behavior of Tricoloured Munia Lonchura malacca (Linnaeus, 1766) and its interaction with pearl millet fields in Villupuram District, Tamil Nadu, India

Study of foraging behaviour of Tricoloured Munia Lonchura malacca and its interaction in pearl millet crop fields was conducted in six villages of Tindivanam taluk, Villupuram district, Tamil Nadu from April to June 2020. A total of six flocks containing 1,640 birds of Tricoloured Munia were enumerated. The number of birds per flock varied from 60 to 800. They never split into small flocks and maintained the same flock size throughout the day. Tricoloured Munias used nine plant species for roosting. Twelve quadrats (0.3 ha) each of 5 m x 5 m size were laid in the pearl millet fields covering six villages. A total of 10,295 spikes were counted in these plots, and of these 3,785 spikes (36.7%) were found damaged by foraging munias. The maximum damage of 99.6% was observed in Thenputhur village. Along with Tricoloured Munia, five other granivorous birds, such as Baya Weaver Ploceus philippinus, Indian Silverbill Euodice malabarica, Common Babbler Turdoides caudata, Rose-ringed Parakeet Psittacula krameri, and White-rumped Munia Lonchura striata were also found foraging without any inter-specific competition. Farmers adopted various traditional bird repellent techniques such as beating utensils, throwing pebbles/soil on the crop, placing scarecrows, tying multi-coloured ribbons, and hanging bottles to chase the birds away.