31 research outputs found
Cassava as an insurance crop in a changing climate: The changing role and potential applications of cassava for smallholder farmers in Northeastern Thailand
No full textApproximately 80 percent of the 22 million people in Northeastern Thailand are engaged in agriculture, and the per capita income of the region is lower than in any other part of Thailand. The major constraint to crop production is rainfall. Although the region has an average annual rainfall greater than 1200 mm, the seasonal distribution of rainfall makes for challenging agricultural cultivation opportunities. The climate is characterized by rainy (May-October) and dry (November-April) seasons. Most (90%) farming is cultivated under rainfed conditions. In addition, most soils are characterized by a sandy texture, high acidity, low organic matter, low level of plant nutrients and low water holding capacity. Due to these conditions, and an increasingly unpredictable climate horizon, cassava has come to play an important economic role for smallholder farmers in the region. The inherent tolerance of cassava to stressful environments, requires minimal care, less investment, and provides greater flexibility in planting and harvesting. Although cassava is grown as a monoculture crop, it can also be grown profitably as a second crop in rice-based cropping systems without supplemental irrigation during the dry season, as well as intercropped in rubber plantations at early growth stages. Given the importance of cassava in farmer income, export values, marketing, and labor, this paper discusses the broader socio-economic and biophysical aspects of cassava due to its important role in future agrarian change for the region
Wood vinegar seed priming improves yield and suppresses weeds in dryland direct-seeding rice under rainfed production
No full textRice seed vigor can affect speed of germination, field emergence and crop yield. These agronomic performance characteristics are essential for sustainable production of rainfed, dry direct-seeding rice. Seed priming may enhance rice seed vigor and agronomic performance for rainfed production. The objective of this study was to evaluate the effect of GA3 and wood vinegar seed priming on seed vigor, seedling performance, and grain yield in farmer’s fields. The experimental design was a splitsplit plot with 4 replications and planted in Thailand between April to December, 2013 and 2014. Two rice cultivars (KDML 105 and RD6) were main-plots, 2 planting methods (broadcast and row) were sub-plots and 3 seed priming treatments (GA3, wood vinegar and untreated control) were subsub- plots. Seed priming enhanced speed of germination and final germination percentage under laboratory and field condition. However, field agronomic performance was strongly influenced by year of production. Wood vinegar primed seeds had greater shoot growth and plant population, while GA3 primed seeds had faster speed of seed germination and greater germination percentage. Total weed biomass was different between rice cultivars and planting methods. At 20 and 40 days after sowing (DAS), weed biomass was dependent on planting method and cultivar. Seed priming significantly reduced weed biomass at 140 DAS in 2013, but not in 2014. Yield-related agronomic performance characteristics of tillers plant-1 and yield in ton ha-1 were significantly higher for primed seed in 2013. Seed priming with wood vinegar is a good, sustainable alternative to improve seedling emergence and increase yield of dry direct-seeding rice. However, the response depends on optimal soil moisture availability during flowering and seed formation.This is a manucript of an article published as Simma, Bubpha, Anan Polthanee, A. Susana Goggi, Boonmee Siri, Arunee Promkhambut, and Petrutza C. Caragea. "Wood vinegar seed priming improves yield and suppresses weeds in dryland direct-seeding rice under rainfed production." Agronomy for Sustainable Development (2017) 37: 56. doi: 10.1007/s13593-017-0466-2. Posted with permission.</p
Effect of Seeding Depth and Soil Mulching on Growth and Yield of Peanut Grown after Rice in the Post-Monsoon Season of Northeastern Thailand
No full textThe experiment was conducted in a farmer's field, Ban Fang district, Khon Kaen province in 1998-1999 to investigate the effect of seeding depth and soil mulching on the growth and yield of peanut grown after rice in the post-monsoon season of Northeastern Thailand. A split plot design was used with mulching and non-mulching as main-plots and seeding depths of 5, 10 and 15 cm as sub-plots. The results showed that deep seeding at 15 cm gave the highest leaf area index, highest total dry matter yield, highest pod number per plant, heaviest 100-seed weight and highest seed yield of peanut. This was attributed to the higher root length density at a deep soil layer provided by deep seeding. Peanut roots in the deep soil layer were capable of exploring a large soil volume for water which remained available throughout the crop cycle. Mulching application showed beneficial effects on growth and yield of peanut only with shallow seeding depth (5 cm)
The Effects of Stake Priming and Planting Method on Early Growth of Cassava Grown under Greenhouse Conditions
No full text The objective of this research is to evaluate the effects of stake priming and planting position on shoot and root growth of cassava, and to improve planting material quality for the early crop establishment period. Three pot experiments were conducted with different bio-activators, soil moisture regimes, and genotypic variations. Results revealed that stake priming increased shoot and root growth of cassava at 21 days after planting (DAP). Stakes soaked in chitosan at a concentration of 10 ml, diluted in ten liters of water for two hours, showed to be the most effective priming method for improving stake quality. Soil moisture regimes applied once at planting at 10% by weight (tension 0.075 bars) and 20% by weight (tension 0.05 bars), had significant effect on root growth of cassava at 21 DAP. Root length and root dry weight were observed higher at 10% level than those of soil moisture at 20% level. Horizontal planting method had a significant effect on root number, and produced greater root length and dry weight of cassava than those of vertical planting method. Shoot and root growth developed different responses to planting method regardless of the cassava’s genotypic variations.
Keywords: cassava, chitosan, planting method, priming, stake soaking, wood vinega
Supplementary Irrigation for Cassava Planted in the Late Rainy Season of Northeastern Thailand
No full textEffects of soaking seed and fertilizer placement on growth and yield of soybean grown after rice in the post-monsoon season in Khon Kaen Province
No full textThe experiment was conducted in a farmer’s field in Ban Fang District, Khon Kaen Province in 1999- 2000. The objective of this study was to investigate the effect of soaking seed in water or not soaking before seeding, and fertilizer placement (surface broadcast at seeding, banding below the seed at seeding and banding beside the plant row 10 days after seeding) on growth and yield of soybean grown after rice in the postmonsoon season. The results showed that soaking seed before seeding had no significant effect on leaf area per plant, total top dry weight, root length density, pod number per plant, seed number per pod, 100-seed weight and seed yield of soybean. However, soybean growth, yield components and seed yields tended to be higher with no soaking. Therefore, soaking seeds in water before seeding had no advantage over no soaking in terms of early emergence and early maturity before the plant was subjected to water stress at grain filling phase. Fertilizer placement had a significant effect on growth nd yield of soybean. Banding application gave higher leaf area per plant, total top dry weight, root length density, pod number per plant and seed yield than those of broadcast application. Banding generally increased leaf N, P and K concentration. There was no significant difference in seed yield between belowband and sideband application. Belowband application tended to produce higher seed yield than that of sideband application. Belowband application at planting saved labour as compared with sideband application. To obtain a satisfactory yield of soybean grown following rice in the post-monsoon season during the rainless period, however, shallow depth of groundwater table to provide upward movement of water to the root zone should be considered
Growth, Yield and Land Use Efficiency of Corn and Legumes Grown under Intercropping Systems
No full textA field experiment was conducted at the experimental farm of Khon Kaen University in 2001. The objectives of this study were to investigate growth, yield and yield components of corn, peanut, soybean and mungbean under intercropping and single cropping, as well as to assess the land use efficiency. Yield and yield components of corn was unaffected by intercropping system. In legume crops; peanut, soybean and mungbean, intercropping systems reduced the leaf area and top dry weight per plant as compared with single cropping. Grain yield of peanut, soybean and mungbean was reduced by 28%, 39% and 51%, respectively, as compared with single cropping. The pod number per plant was the most affected by intercropping among the yield components. However, corn-legume intercropping increased land use efficiency by 48% to 66% depending on legume species. Corn-peanut intercropping gave the highest land use efficiency. The effects of light penetration and nutrient competition are discussed
Influence of low light intensity on growth and yield of four soybean cultivars during wet and dry seasons of northeast thailand
No full textLong-term change in rainfall distribution in Northeast Thailand: Will cropping systems be able to adapt?
No full textClimate vagaries and the lack of irrigation, frequently combined with coarse-textured sandy and unevenly distributed saline soils, explain low crop yields and the endemic relative poverty of the rural population in Northeast Thailand (NET). Local and regional trends in agriculturally-relevant rainfall variables were investigated using the Mann-Kendall test, modified to account for serial correlation, and applied to 17 stations across NET, and the regional average Kendall's statistic. Limited changes in rainfall frequency, intensity and seasonality are observed at individual stations over the study period (1953–2004). But we found a significant regional trend toward a wetter dry season. Based on an intimate knowledge of the local farming systems, we discuss the cropping systems adaptation to these rainfall changes. If the wetting of the dry season extends in the future, as expected according to most climate projections, households would not find it difficult to adapt, except for the problems caused by temperature rise, mainly due to their renowned adaptive capacity and high mobility that historically produced diverse and resilient rural livelihood systems
