Effect of fertility levels and nano-nitrogen on growth and yield of pearl millet [Pennisetum glaucum (L.) R. Br. emend Stuntz]

Introduction

Pearl millet [Pennisetum glaucum (L.) R. Br. emend Stuntz] is the most important staple food of majority of poor and small land holders in Asia and Africa. It is consumed as feed and fodder for livestock. It produces nearly half of all millets on the planet. Behind wheat, rice, corn, barley and sorghum, it is the world's sixth most valuable cereal crop. After rice, wheat and maize, pearl millet is India's fourth most widely cultivated food crop. It occupies an area of 6.93 million ha with an average production of 8.61 million tonnes and productivity of 1243 kg ha -1 . In rajasthan pearl millet occupies area of 4.54 m ha -1 with annual production of 5.89 m t -1 and productivity of 1296 kg ha-1 (Anonymous, 2022-23) [1] . Rajasthan, Maharashtra, Uttar Pradesh, Gujarat and Haryana are the main pearl millet producing states. Nitrogen increases process of photosynthesis, leaf area duration, leaf area production, net assimilation rate, food quality and crop yield. Phosphorus plays a vital role in increasing crop yield because it improves crop quality and provides resistance against diseases.

Potassium plays important role in stomata activity, transport of sugars, water and nutrient, synthesis of protein and starch. Nano fertilizers are the most important field of agriculture has been giving the attention of the soil scientists as well as the environmentalists due to its capability to increase yield and improve soil fertility. Nanotechnology can reduce the rate of fertilizer nutrients loss through leaching and increase their availability to plants which ultimately leads to reduced water and soil pollution. Nowadays, nano fertilizers are emerging as an alternative to conventional fertilizers (Veronia et al., 2014). Nano materials are defined as materials with a single unit between 1 and 100 nm in size in atleast one dimension (Liu and Lal, 2015) [2] and having a both positive and negative charge on same particle that led to improve uptake of other nutrients by holding those nutrients in soil against different losses.

Materials and Methods

The experiment was conducted during kharif 2023-25 at Research Farm, School of Agriculture, Suresh Gyan Vihar University, Jaipur (Rajasthan). Geographically, the study area is located at 75° 51'44" E longitude and 26°48'35''N latitude and altitude of 427 m mean sea level. This region experiences subtropical climatic conditions, with mild winter and summer temperatures and high relative humidity from July to September. The present experiment consisting of 16 treatment combinations was laid out in Factorial Randomized Block Design. The experiment consisted sixteen treatments viz., two factors with where four fertility levels are (Control, 50%, 75% and 100% RDF) and four levels of nanonitrogen foliar spray are (Control, 1.5 ml l-1, 3.0 ml l-1 and 4.5 ml l-1). Seeds of Pearl millet variety 'RHB-233' were sown manually by 'Kera' method at rate of 4 kg ha -1 maintaining row distance of 45 cm and plant to plant distance 15 cm placed at depth of 5 cm and sowing was done at 11 th July 2024. Fertilizers were placed beneath the seed, after placing the seed in furrows it was covered with soil for uniform germination and to protect from bird damage. Pearl millet crop was harvested from net plot of 3.0m x 2.7 cm = 8.1 m 2 separately, and taken from the particular plot when it reached physiological maturity. The plants from net plot were cut close to the ground, Cut the ear from plant, and spread out on the threshing floor to dry in the sun.

Results and Discussion

Effect of fertility levels and nano-nitrogen

The application of different fertility levels and nano-nitrogen has a considerable impact on the growth parameters of pearl millet as demonstrated by clear data, The application of 75% RDF and nano-N foliar spray @ 3.0 ml-1 significantly increased the plant height at 60 days after sowing and at harvest dry matter accumulation at 60 DAS and at harvest, leaf area index and chlorophyll contain over control (Table 1). Pandit et al., (2020) [3] assessed the influence of fertility levels, plant density, and seedling age on transplanted pearl millet (Pennisetum glaucum L.) and they recorded that significantly higher plant height (236.9 cm), leaf area index (3.9), dry matter accumulation (1235.6 g/m2), tillers/hill (4.2) at harvest under the fertility levels of F3 (150:75:75 kg NPK/ha), but being statistically at par with F2 but superior. Fertility level of F3(150:75:75 kg/ha) gave higher tillers/plant at all the crop growth stages i.e. at 30 DAT (7.09), 60 DAT (6.79) and harvest (4.21), which was statistically at par with F2(120:60:60 kg/ha) but superior over F1(90:45:45 kg/ha). Parihar et al., (2012) [4] at IARI, New Delhi reported that all the growth attributes of pearl millet, namely, plant height, LAI, total number of tillers and dry matter accumulation were significantly higher with 30 kg N + 20 kg P2O5/ha and 6 t/ha FYM over control, 30 kg N + 20 kg P2O5 /ha and sole application of 6 t/ha FYM but remained at par with 60 kg N + 40 kg P2O5/ha. It is probable to correlate the overall increase in crop growth caused by nano-nitrogen application to improved root development of plant in the soil. The plant height varied from 128.5 to 151.4 cm among all the treatments. Highest plant height (151.4 cm) was recorded with application of 100% RDF and Nano-N foliar spray @ 4.5 ml l -1 (148.5 cm) which was superior over other treatments. The Highest dry matter accumulation in pearl millets plant (118.96 g plant-1) was registered with application of 100% RDF and Nano-N foliar spray @ 4.5 ml l -1 (118.35 g plant-1) which was significantly superior over all treatments. The leaf area index was found highest (3.21) in Nano-N foliar spray @ 4.5 ml l -1 and 100% RDF (3.13) treatment which was significantly superior over all treatments. The chlorophyll content was found highest (2.84) in Nano-N foliar spray @ 4.5 ml l -1 and 100% RDF (2.89) which was significantly superior over all treatments. The number of effective tillers/plant were significantly increased under treatment 100% RDF which was superior over all treatments. The effective tillers range 2.49 to 2.87. The ear head length of pearl millet was significantly increased under 100% RDF and Nano-N foliar spray @ 4.5 ml l -1 as compared to other treatments. The ear length range registered between 18.60 and 22.41. The grain weight earhead -1 of pearl millet was significantly influenced by different treatments. Planting of pearl millet with 100% RDF and Nano-N foliar spray @ 4.5 ml l -1 recorded significantly higher grain weight earhead -1 (7.77 g). The different fertility application practices had significant effect on grain yield. Significantly higher grain yield of 2273 kg/ha was recorded under Nano-N foliar spray @ 4.5 ml l -1 with 100% RDF. The Stover yield recorded after harvest of the pearl millet crop as influenced by fertilization. The stover yield is highest 4596 kg/ha was recorded under Nano-N foliar spray @ 4.5 ml l - 1 . The biological yield of pearl millet was increased due to 100% RDF over control. Significantly superior biological yield was obtained 100% RDF over control. The harvest index of pearl millet was not influenced significantly due to fertilization. However, higher and lowest harvest index was recorded under 100% RDF and control respectively.

Conclusion

Based on results of one year experiment, it may be concluded that application of RDF and nano-nitrogen produced significantly higher seed, straw and biological yield and net returns as compared to other treatments. Therefore, application of 100% RDF may be recommended for higher production and profitability of pearlmillet under semiarid condition of Rajasthan.

References

1. Anonymous. Annual report: All India Coordinated Research Project on pearl millet. Jodhpur; 2023.
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3. Pandit SK, Prasad S, Singh MK, Singh YK, Niranjan IK, Kumar R. Effect of fertility level, plant density and age of seedling on transplanted pearl millet (Pennisetum glaucum). International Journal of Current Microbiology and Applied Sciences. 2020;9(6):1124-1131.
4. Parihar CM, Rana KS, Jat ML, Jat SL, Parihar MD, Kantwa SR, et al. Carbon footprint and economic sustainability of pearl millet-mustard system under different tillage and nutrient management practices in moisture stress conditions. African Journal of Microbiology Research. 2012;6(23):5052-5061.
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