Farmer-participatory evaluation of mechanized dry direct-seeding technology for rice in northeastern Thailand

Abstract

Rice technologies that are designed to reduce risks due to climate variations, improve productivity, or overcome labor scarcity are important in tropical Asia. The objective of this study was to evaluate mechanized options for dry direct-seeding of rice in terms of the productivity and production costs in rainfed lowlands. In a series of on-farm research trials over 3 years in Ubon Ratchathani province, Thailand, we compared seeding by seed drills mounted on two-wheel tractors with manual broadcast seeding. Demonstration trials of seed drills and site-specific nutrient management in 2017 with 11 of 26 participating farmers produced 2.50 t ha −1 of grain yield, but unexpected heavy storms forced the other 15 farmers to switch from dry to wet direct-seeding or manual transplanting. The seed drills produced 32% higher grain yield than manual broadcast seeding (3.3 vs. 2.5 t ha −1) in 2014, and 14-24% higher yield (3.3-3.6 vs. 2.9 t ha −1) in 2015. Mechanized seeding enabled seeding rate reduction by 50% in 2014 and by 52-61% in 2015, resulting in lower production costs than with manual seeding. Our results suggest that mechanized dry direct-seeding of rice with improved nutrient management can enhance farmer livelihoods in rainfed environments in northeastern Thailand. This approach can significantly reduce production costs compared with manual transplanting, while maintaining or increasing productivity compared with conventional manual broadcast seeding.

Soil Organic Carbon in Sandy Paddy Fields of Northeast Thailand: A Review

“…Haefele and Konboon [111] proposed a site-specific nutrient management approach based on toposequence and field-specific ingenious nutrient supply to choose the most optimum fertilizer for the farmers. The adoption of site-specific nutrient management combined with mechanized dry direct-seeding in the rainfed lowland area, as studied in Sansen et al [100], shows high potential for decreasing the cost of rice cultivation. In sandy soils with a clay content below 5%, the response to inorganic fertilizer is often lower than in the finer texture soils [112].…”

Enriched-GWAS and Transcriptome Analysis to Refine and Characterize a Major QTL for Anaerobic Germination Tolerance in Rice

“…The panel consisted of 62.4% (219) accessions with white pericarp, 30.4% (107) red colored pericarp, and 7.1% (25) no observation recorded for pericarp color (Figure S3). Most accessions were from East Asia (126), South Asia (108), and South East Asia (87); while the rest were from Africa (13), America (10), Middle East (1), and unknown (6). They were mostly indica (93.7%) and some aus (5.4%) (Supplementary File S3).…”

“…There is substantial opportunity for change, particularly in new areas opening up for cultivation, provided management systems and adapted cultivars are available. Over the last decade, DS rice has become increasingly popular across Asia due to its low-input demand and labor and cost savings [ 5 , 6 ]. One of the world’s leading rice producers, India, now has more than 50% of its rainfed production under DS and Thailand, one of the leading rice exporters, has most of its rainfed rice under DS conditions.…”

Fertilizer responsiveness of high-yielding drought-tolerant rice in rainfed lowlands

“…This approach has been extensively assessed in on-farm trials during the last two decades (Buresh et al, 2019;Pampolino et al, 2007). These studies show the higher N fertilizer-use efficiency (yield increase per kg of N applied) in this practice compared with the conventional practice, and thus increased farmer income by more than 100 USD ha −1 throughout tropical Asia (Banayo et al, 2018;Sansen et al, 2019).…”