Journal of Agriculture and Rural Development in the Tropics and Subtropics (JARTS)
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Variation in the Response of Seed and Embryonic Axes to Incubation Temperature Gradients during Seed Treatments in Pearl Millet and Sorghum
Get PDFIncubation temperature during the presowing soaking of seeds plays a significant role in determining the rate and characteristics of post-treatment germination. Three experiments were conducted on sorghum (Sorghum bicolor L Moench) and pearl millet (Pennisetum glaucum L. R. Br.) genotypes to determine the influence of constant, alternating, ascending and descending temperature regimes on germination characteristics of seeds after treatment. Incubation temperatures ranging from 10 to 35C were applied as well as alternating the magnitude and range of day/night temperatures. A third experiment tested a 3-day temperature gradient and its impact on germination and seedling characteristics. All three incubation temperature regimes were combined with various hormonal and mineral seed soaking treatments to test for possible interactive effects. Temperature did not affect the final germination percentage of seeds but influenced the germination rate. Constant temperatures of 20 or 25C induced higher germinative capacity than alternating or constant temperatures of higher or lower magnitude. Increasing the variance in day/night temperature reduced the rate of germination. Incubating seeds during soaking treatments at a constant 20C for 3 days yielded better germination characteristics than a thermal gradient of 25/20/15C. An 8 g l1 NaCl treatment induced greater plumule (shoot) growth than non-treated counterparts and treating seeds with GA3 or salts improved germination characteristics and synchrony of treated seed lots
Effects of Mineral N and P Fertilizers on Yield and Yield Components of Flooded Lowland Rice on Vertisols of Fogera Plain, Ethiopia
Get PDFDespite its very recent history of cultivation in Ethiopia, rice is one of the potential grain crops that could contribute to the efforts for the realization of food security in the country. However, the scientific information available with regards to the response of flooded rice to N and P fertilizers for its optimum production on Vertisols of Fogera Plain is very limited. Therefore, a field experiment was conducted on Vertisols of Fogera plain, northern Ethiopia to study the yield and yield components response of rice and to establish the optimum N and P fertilizer levels required for improved grain yield of flooded rice. Six levels of N (0, 30, 60, 90, 120 and 150 kg ha−1) and five levels of P (0, 13.2, 26.4, 39.6 and 52.8 kg ha−1) laid down in a randomized complete block design with four replications were used as treatments. Nitrogen was applied in two equal splits (50% basal and 50% at maximum tillering) as urea and the entire dose of P was applied basal as triple super phosphate at sowing. The main effects of N and P fertilizer levels showed significant differences (P ≤ 0.01) for all yield and yield components studied. The effects of N by P interaction were significant only for grain yield (P ≤ 0.05), number of panicles per m2 (P ≤ 0.01), number of spikelets per panicle (P ≤ 0.05) and plant height (P ≤ 0.01) among the different yield and yield components studied. Application of N and P significantly (P ≤ 0.01) increased grain yield of rice up to the levels of 60 kg N and 13.2 kg P ha−1. However, maximum grain yield (4282 kg ha−1) was obtained with the combined application of 60 kg N and 13.2 kg P ha−1, and the yield advantage over the control was 38.49% (1190 kg ha−1). Moreover, application of both N and P fertilizers have increased the magnitudes of the important yield attributes including number of panicles per m2, number of spikelets per panicle, panicle length, dry matter accumulation, straw yield and plant height significantly (P ≤ 0.01). Besides, grain yield was positively and significantly associated with number of panicles per m2 (r = 0.61∗∗), number of spikelets per panicle (r = 0.49∗∗), panicle length (r = 0.54∗∗), dry matter accumulation (r = 0.46∗), thousand grain weight (r = 0.41∗) and harvest index (r = 0.39∗). These indicate that N and P application increased grain yield of rice by positively affecting the important yield components of the crop. Therefore, taking the findings of the present study into consideration, it may be tentatively concluded that the farmers at the Fogera plain may apply a combination of 60 kg N and 13.2 kg P ha−1 to improve the grain yield of flooded lowland rice cultivated on heavy black clay soils (Vertisols) under rain fed conditions
Influence of Topping, Side Branch Pruning and Hill Spacing on Growth and Development of Cotton (Gossypium barbadense L.) in the Southern Guinea Savanna Location of Nigeria
Get PDFTwo field experiments were carried out at the Teaching and Research Farm, University of Agriculture, Makurdi, Nigeria, during 2000 and 2001 seasons on Pima S2 cotton cultivar, to study the effects of hill spacing of 30, 35 and 40cm (plant population) and plant growth alteration treatments i.e. topping, side branch pruning at 120cm height, topping + pruning at 100cm height, topping + pruning at 120cm height on some vegetative and fruiting habits, earliness and seed cotton yield and its components. Generally the combined data clarified that wider hill spacing increased number of monopodia, main stem internodes, sympodia, additional fruiting branch bolls, retended bolls, fruiting sites, percentage of bolls on vegetative branches, open bolls, boll weight and seed cotton yield. While it decreased final plant height, number of aborted sites, days to first open boll, earliness percentage and number of unopen bolls. However, plant alteration treatments had a positive effect on most studied traits and reversely depressed number of monopodia, aborted sites and earliness percentage compared with the control. Within plant alteration treatments, there were significant divergences. The results indicated that topping plants at 120cm height increased number of retended bolls, fruiting sites, days to first open boll, open boll, unopen bolls and seed cotton yield. Side branch pruning at 120cm height increased final plant height, monopodia, main stem internodes, sympodia, earliness percentage and boll weight. Topping + pruning at 100cm height only decreased number of aborted sites. Topping + pruning at 120cm height increased additional fruiting branch bolls, percentage of bolls on vegetative branches, boll weight and seed cotton yield. Topping at 120cm height and 40cm hill spacing resulted in the highest number of retended bolls and seed cotton yield
Sawah First! The Cultural Ecology of Alang-Alang in a Rain Forest Margin Community
Get PDFImperata cylindrica, or alang-alang as it is often referred to in writings on SE-Asia, is one of the most intensively studied weeds of the world. In investigating alang-alang related problems in a small holder community in the vicinity of the Lore Lindu National Park on the island of Sulawesi, Indonesia, this paper challenges some common claims about the origins, attached values and future perspectives of alang-alang. The sources of imperata infusion in the research area are neither linked to population pressure, nor to inadequate cropping techniques in dry land cultivation. Rather, alang-alang expanded as a reaction to the development of the wet rice sector which absorbs most of the time and labour of the farmers.Of ten being forced to abandon their dry land plots in order to manage their wet rice fields, farmers create ideal conditions for the grass to expand.Ho wever, whereas on the one hand alang-alang represents a major element of “criticality”, the alang-alang plot as such offers important opportunities provided by other plants growing naturally in imperata sites.A culturally defined preference for rice subsistence as well as an orientation aimed at securing survival rather than enhancing profitability make an effective control of the weed difficult
Host Suitability of Crops under Yam Intercrop to Root-knot Nematode (Meloidogyne incognita Race 2) in South-Western Nigeria
Get PDFTwelve crops commonly grown in association with yam in South-Western Nigeria were evaluated for resistance to root-knot nematode Meloidogyne incognita (Kofoid and White 1919) Chitwood 1949, race 2 infection using the quantitative modification by Sasser et al. (1984) of host suitability designations of Canto-Saenz (1983) for plants infected with root-knot nematode in 1998 and 1999 planting seasons. Observations, based on gall indices and recovery of the juvenile larvae from the roots and soil indicated that Abelmoschus esculentus, Corchorus olitoris cv Angbadu and Sphenostylis stenocarpa cv Nsukka Brown were highly susceptible, while Arachis hypogaea cv UGA 4, Cajanus cajan cv Cita-2, Cucumis melo cv Bara To139, Manihot esculenta cv TMS 30572, Sorghum bicolor and Zea mays cv DMR-LSR-Y were hyper-susceptible to Meloidogyne incognita race 2 with reproductive factor and gall index of ≤1 and ≥2 respectively. Crotalaria juncea, Mucuna cochinchinensis and Stylosanthes gracilis were resistant to Meloidogyne incognita race 2 with reproductive factor and gall index of ≤1, ≤2 and ≥2 respectively. These intercrops if planted on yam mounds will play a prominent role in altering the populations of root-knot nematode Meloidogyne incognita race 2
Contracting Tobacco Growing in Turkey
Get PDFTobacco is a very important product in Turkish agriculture and economy. As a result of a change in the privatization policies, the support of the state in tobacco (production) is abrogated. With the introduction of the new law (No: 4733) the marketing system of tobacco has totally changed and has been replaced with the auction system and contract production. In this study the tobacco production in the year 2002 is scrutinized in order to evaluate the effect of the contract production system on tobacco production by means of a field research in Manisa. The auction system will be launched in 2003, that is why it is not included in this study. According to the research findings the majority of the producers are not satisfied with the contract production system as the contractions are being prepared one-sided and producers do not have the right to haggle. The problems that occured in the application of this new law are suggested to be eliminated by adapting the auction system, akin to the one in the USA, which enables producers to partake in the marketing of the product
Technical Efficiency of Resource Use in the Production of Irrigated Potato: A Study of Farmers Using Modern and Traditional Irrigation Schemes in Awi Zone, Ethiopia
Get PDFBased on cross-sectional data collected from randomly selected 80 farmers in four districts of Awi zone in North-western Ethiopia, this study examines the technical efficiency of farmers in the production of irrigated potato. The stochastic frontier production function, which considers deviation from the frontier to be due to the effect of technical inefficiency and random noise, is used for data analysis. Technical efficiency of farmers was estimated independently for the farms under modern irrigation schemes and traditional irrigation schemes. Using likelihood ratio test, Translog production function is found to be an adequate representation of the production behavior of farms under the two types of schemes. The mean level of technical efficiency was found to be 77 percent and 97 percent respectively for modern and traditional schemes. Therefore, improving the level of efficiency could raise productivity under modern schemes, whereas improving productivity under traditional schemes needs introduction of new technology as the farmers’ level of production has approached the frontier. Irrigation experience, commodity rate of production and size of livestock are found to be the important variables that determine the level of efficiency
Variety and Cultivation-practice Influences on the Growth Characteristics and Yield of Maize (Zea mays L.) under Drought Stress at Flowering
Get PDFIn northeast Thailand, maize (Zea mays L.) is mainly grown under rainfed conditions. In this region, frequent dry spells are often the cause of periodic drought-stress that leads to decreased yields, especially during the critical growth stages. The objective of the study was to identify and assess variety and cultivation-practice effects on the growth and yield of maize under temporary drought stress induced during the flowering stage. Under controlled soil-moisture conditions, three varieties (Suwan5 - open-pollinating; Big717 and Big949 - single-cross hybrids) and five cultivation practices (conventional (CT); mungbean (Vigna radiata (L.) Wilzek) residue (Mn); spineless mimosa (Mimosa invisa) live mulch (Mi); manure (Ma); and plastic mulch (Pl) were studied for two cropping seasons. There were significant variety differences, apparently independent of the cultivation practices. The two hybrid varieties produced significantly higher grain yields than the open-pollinating variety, i.e., Big717 Big949 Suwan5. The effects of cultivation practices were less prominent, with the exception of Suwan5, for which Mn, Mi, and Ma significantly reduced grain yields compared to CT and Pl. Big717 showed no significant differences between the treatments; Big949 showed significant treatment response only for the second crop, particularly for the Ma treatment. Overall, the highest average yields were produced by Pl; the lowest by Ma. However, there were no significant differences for the total aboveground biomass between cultivation practices, but between varieties -i.e., Suwan5 and the two hybrids. The two hybrids had clearly higher harvest indexes (HI) than the open pollinating variety. For Suwan5 and Big949 HI was consistently lowest with the Ma treatment.Th e general trend of the tasseling-silking interval (TSI) was Big949 Suwan5 Big717. For Big717, TSI was not affected by any cultivation practices. For the other two varieties, Ma showed longest TSI. Suwan5 grew more vigorously than the other varieties at the early vegetative stage. Within the varieties, the tallest plants were observed with Ma. The effects of cultivation practices on the grain yield were less prominent than the variety effects; in some cases the practices, particularly Ma, even had a negative effect on the yield. Therefore, variety selection is still a potential management tool that can effectively control the effects of drought stress on the plants. It is however highly recommended that further studies should investigate plant responses for drought-stress periods during other growth stages and with different degrees of drought stress. On-farm trials under uncontrolled drought-stress conditions should be also carried out
Effect of Irrigation Regime on Growth and Development of Two Wheat Cultivars (Triticum aestivum L.) in the Nigerian Savanna
Get PDFField trials were conducted at irrigation research stations of the Institute for Agricultural Research, Kadawa (11° 39’N, 08° 27’E, 500m asl). The objective was to study the effect of irrigation regime (60, 75 and 90% Available Soil Moisture (ASM) on the growth and yield of two recently introduced wheat cultivars (Siete cerros and Pavon 76). The result revealed that increase of irrigation regime from 60 to 90% ASM did not significantly affect most of the growth, yield and yield parameters evaluated in the study. Each increase in irrigation regime however increased days to maturity, water use and thermal time but decreased water use efficiency. Pavon 76 produced superior grain yield than Siete ceros only in one season. Pavon 76 had a higher LAI, more tillers and spikes/m2 and larger grain size, but had shorter plants, lower grain weight and grain number/spike and matured earlier than Siete cerros. Irrigation level of 60% ASM is recommended for both varieties in the Sudan savanna ecology. At this ASM the highest water use efficiency of 4.0-4.8kg/mm/ha was obtained and grain yield was not significantly compromised. Grain yield was more strongly correlated with grain weight per spike than with grain number per spike
Degree of Adaption of Lianas (Parthenocissus quinquefolia (L.) and Campsis radicans (L.)) to the Environmental Conditions of Towns
No full textResults of anatomic investigations are discussed, being carried out at leaves of lianas (Parthenocissus quinquefolia (L.) and Campsis radicans (L.)), growing under environmental conditions of towns. It could be found from the result, that xerographic phenomenons are reflecting the environmental conditions in towns. The effects of environmental pollution can be found at necrotic cells in the mesophyll of leaves. Demages of the leaves could be found by only visual investigations of the leaves