Effect of Gluconacetobacter diazotrophicus inoculation and reduced nitrogen fertilizer on yield and growth parameters of rice varieties

Abstract

This study aimed to investigate effects of nitrogen (N) fertilizer rates and inoculation of rice seeds with N-fixing bacterium Gluconacetobacter diazotrophicus on the growth parameters and yield of OM5451 and OM6976 rice varieties in the Vietnamese Mekong Delta region. Nitrogen fertilizer rates of 50 kg N.ha-1 and 100 kg N.ha-1 were used, with latter reflecting farmer practice. Three rice seed inoculation methods were also employed: Seeds soaked in water for 24 hours and allowed to stand for 30 hours (control) (B0); Seeds soaked in water for 24 hours and inoculated with G. diazotrophicus for 30 hours (B1); Seeds soaked with G. diazotrophicus in water for 24 hours and allowed to stand for 30 hours. Applying 50 kg N.ha-1 without combining with NFB bacterium in this experiment generally resulted in less tillers, shorter plants, a lower SPAD index, and lower grain yield. Combining G. diazotrophicus bacterium with reduced N fertilizer of 50 kg N.ha-1 demonstrated rice growth and yield may be maintained in both varieties compared to 100 kg N.ha-1. These results providing a firm foundation for future research of adding NFB to paddy soils to decrease the N fertilizer requirement.

Reducing nitrogen fertilizer combined with biochar amendment improves soil quality and increases grain yield in the intensive rice cultivation system

“…It explained why the organic carbon and available N contents in the treatment that applied 50 kg N ha -1 did not differ significantly compared to the treatment that applied 100 kg N ha -1 . This results were in agreement with Dung et al (2021) studied the effects of reduced N fertilizer on two rice varieties in the VMD region. Dung et al (2021) reported that applying 50 kg N ha -1 could maintain the number of tillers, rice height, and grain yield of OM5451 and OM6976 compared to the traditional cultivation applied 100 kg N ha -1 .…”

“…This results were in agreement with Dung et al (2021) studied the effects of reduced N fertilizer on two rice varieties in the VMD region. Dung et al (2021) reported that applying 50 kg N ha -1 could maintain the number of tillers, rice height, and grain yield of OM5451 and OM6976 compared to the traditional cultivation applied 100 kg N ha -1 . pH is the most important factor in the soil has directly affected the availability of soil nutrients (Weil and Brady, 2017).…”

“…In the intensive rice production system in the Vietnamese Mekong Delta (VMD) region, farmers often use a large amount of N fertilizer to gain a high yield (Dung et al, 2021). However, this application could increase fertilizer costs and high-risk environmental pollution.…”

Effects of pre-sowing seed treatments on rice yield, grain quality and soil chemical properties in salt-affected soils

“…Some previous studies showed that the seeds treatments did not significantly affect the rice germinated rate (Adhikari et al, 2013;Hao et al, 2016;Sarkar et al, 2019). In normal conditions, the germination rate of rice depends mainly on the variety (Ju et al, 2000;Dung et al, 2021) Figure 1. The germination rate of rice seeds under different seeds incubation duration…”

Effects of Land Preparation and Iron-coated Rice Seeds on Yield, Growth Parameters, and Soil Properties in the Mekong Delta, Vietnam

“…Fe-coated primed dry rice seeds, a technology developed in 2004, and untreated rice seeds have both been sown onto paddy fields for comparison studies (Yamauchi, 2004). Some previous studies have shown that a change in the seed inoculation methods did not significantly affect the germination rate of rice seeds (Mori et al, 2012;Adhikari et al, 2013;Hao et al, 2016;Sarkar et al, 2019;Dung et al, 2021;Dung et al, 2022). Mori et al (2012) tested the germination rate of Fe-coated rice seeds under Vietnam Journal of Agricultural Sciences…”