Seed Priming with Potassium Nitrate and Gibberellic Acid Enhances the Performance of Dry Direct Seeded Rice (Oryza sativa L.) in North-Western India

Abstract

Poor early growth and uneven crop establishment are reported as the major bottlenecks in wide-scale adoption and optimal yield realization of dry direct-seeded rice (DSR). Seed priming can potentially help overcome these problems in DSR. Therefore, laboratory and field studies were conducted at Punjab Agricultural University, Ludhiana, India, during kharif/wet-season 2018 and 2019 to evaluate the effect of different priming techniques on germination, establishment, growth, and grain yield of rice under DSR conditions. The following priming treatments were evaluated: dry non-primed seed (control), hydropriming with distilled water, halopriming with 2.0% potassium nitrate, hormopriming with 50 ppm gibberellic acid (GA3), and osmopriming with polyethylene glycol (PEG)(−0.6 MPa), each with 12 and 24 h priming duration. In 2019, priming treatments were tested under two DSR establishment methods—conventional DSR (sowing in dry soil followed by irrigation) and soil mulch DSR (locally known as vattar DSR) (sowing in moist soil after pre-sowing irrigation), whereas in 2018, priming treatments were evaluated under conventional DSR only. In both years, halopriming and hormopriming resulted in a 7–11% increase in rice yields compared to non-primed dry seed (control). Osmopriming resulted in a 4% yield increase compared to control in 2018 but not in 2019. The higher yields in halopriming and hormopriming were attributed to higher and rapid germination/crop emergence, better root growth, and improvement in yield attributes. Priming effect on crop emergence, growth, and yield did not differ by DSR establishment methods and duration of priming. Conventional DSR and soil mulch DSR did not differ in grain yield, whereas they differed in crop emergence, growth, and yield attributes. These results suggest that halopriming with 2.0% potassium nitrate and hormopriming with 50 ppm GA3 has good potential to improve crop establishment and yield of rice in both conventional and soil mulch DSR systems.

Seed priming with selenium and zinc nanoparticles modifies germination, growth, and yield of direct-seeded rice (Oryza sativa L.)

“…Dry DSR could be more advantageous over the other two methods 8 , 9 due to less time required for sowing, thus economizing time and labour, and saving water. Though PTR is the main rice transplanting system in Asia including India, DSR has now been gaining popularity 10 – 13 . For example, in China, DSR now covers 28% of the total rice area 14 , while in Sri Lanka and Malaysia, areas under DSR are > 93% (1.03 M ha) and 95% (0.67 M ha) respectively of their respective total rice area 15 .…”

Effect of potassium nitrate on germination physiology of magnesium nitrate primed and non-primed rice seeds var. Swarna

“…In addition, Ali et al (2021) reported that there was a significant increase in final emergence (%), mean emergence time, and physiological attributes were observed in tomato while primed with 0.75% KNO 3 . Moreover, Dhillon et al (2021) noted that halo-priming with 2.0% KNO 3 in dry direct seeded rice were attributed to higher and rapid germination/crop emergence, better root growth, and improvement in yield parameters. In the present study it has also been realized that no rooting was observed except radicle in the non primed seedlings during study periods whereas, the seedlings from primed seeds generate more number of roots from the crown region.…”

“…Priming also minimizes effect of en-vironmental stress during the time of germination and ultimately leads to higher seedling emergence and stand establishment with vigorous growth (Marthandan et al, 2020;Ali et al, 2021). Such kind of pre-metabolic biological activities of priming are helpful for farmers because it reduces the time of emergence, cost of repeated seeding, fertilization and additional irrigation on treatment with various chemicals or bio-chemicals in different field crops and horticultural crops (Hussain et al, 2015;Ruttanaruangboworn et al, 2017;Ali et al, 2020;Acharya et al, 2020;Dhillon et al, 2021).…”

Emerging Issues and Potential Opportunities in the Rice–Wheat Cropping System of North-Western India

“…Conventional rice cultivation in the RWCS is characterized by intensive puddling followed by transplanting of 25- to 30-day-old seedlings, maintaining standing water in paddy fields for 2 weeks, and thereafter re-applying irrigation 2 days after the ponded water has disappeared due to infiltration into the soil ( Anonymous, 2020 ; Dhillon et al, 2021 ). This practice offers some benefits, such as competitive advantages against weeds and poor oxygen diffusion that restricts the germination of weeds, assured anaerobic conditions with a neutral soil reaction, and greater availability of nutrients, such as iron ( Bhatt and Kukal, 2015 ).…”

“…The continuous use of a single herbicide in rice for the control of Echinochloa spp. resulted in the emergence of new hardy weeds like Leptochloa chinensis (L.) Nees, Cynodon dactylon (L.) Pers., Ischaemum rugosum Salisb., Paspalum distichum L., Ludwigia hyssopifolia (G. Don) Exell, Eclipta prostrata L., Cyperus rotundus L., Cyperus iria L., Cyperus difformis L., and Fimbristylis miliacea (L.) Vahl ( Mahajan et al, 2012 ; Shekhawat et al, 2020 ; Dhillon et al, 2021 ). Due to the monocropping of the RWCS, the infestation of Phalaris minor Retz.…”