Search

The serious problems of sandy soils for crop development are low water-holding capacity, nutrient retention, and low content of all nutrients. The objective of the study was to increase the nutrient content of sandy soil and evaluate nutrient types that mostly affect the high shallot yield with reasonable economic values. The field experiment was conducted on the upland sandy loam soil. Six treatments consisting of complete nutrients, N-, P-, K-, Mg- and S-omission tests were arranged in a randomly completed block design with four replicates. The observed parameters included soil physicochemical properties, tissue nutrient content, growth, yield, and input-output of shallot cultivation. The results showed that N, P, K, Mg and S application successfully increased shallot bulb, achieving 11.43 t ha−1 on sandy soil. The order of shallot tissue content was K > N > P~Mg > S, where the S, P, N, and Mg are limiting factors, as revealed by significantly lower relative yield (varying from 79 to 88%). The highest weight loss during storage occurred for S-omission treatment (40 to 60%), indicating insufficient S tissue is the most responsible for the quality of shallot. The complete nutrient treatment gave the highest income (7446.09 USD ha−1) with a revenue cost ratio of 2.41 compared to other treatments. The tolerance limit for price reductions that do not cause losses was 58.59%.

Soil salinity is one of the major obstacles that is limiting the growth and yield of groundnut. This study aims to investigate the effect of growth-promoting fungi, Trichoderma, on groundnut plants that were cultivated in saline conditions. Five different Trichoderma isolates were grown in four different NaCl concentrations. Selected Trichoderma were then applied to the groundnut seeds and their growth and development were monitored during the study. Growth inhibition, volatile organic compounds, chlorophylls, carotenoids, total phenolics and flavonoids, and minerals were assessed between the Trichoderma treatments. Increasing the salt concentration from 0.25–0.75 M decreased the growth of the Trichoderma isolates. The amounts and profiles of the volatile organic compounds from the T. asperellum isolate were significantly different to those in the T. virens isolate. In the vegetative growth stage, increased chlorophyll content was recorded in both the T. asperellum and T. virens-treated groundnut. The leaves that were obtained from the groundnut that was treated with T. virens T.v4 contained significantly higher indole-3-acetic acid (420 µg IAA/g) than the same plants’ roots (113.3 µg IAA/g). Compared to the control groundnut, the T. asperellum T.a8-treated groundnut showed increased phenolics (31%) and flavonoids (43%) and increased shoots and biomass weight at the generative growth stage. This study demonstrates that Trichoderma, with their plant growth promotion ability, could potentially be used to improve the growth of groundnut growing under salinity stress. Importantly, salt-tolerant Trichoderma could be regarded as a beneficial and sustainable way to improve the survival of salt-sensitive crops.

Centella asiatica is an herbal plant with many health benefits due to the content of asiaticoside compounds. Factors affecting asiaticoside content are altitude, soil texture, and soil nutrient status. This research aimed to identify the effect of zeolite, P2O5 fertilizer, and soil media from different altitudes on C. asiatica. The research was conducted in a greenhouse from August 2017–June 2018. The experimental design was a factorial, completely randomized design with three factors and four replications. The first factor was soil media that originated from 100, 450, and 900 m above sea level (asl), the second factor was the dose of P2O5 fertilizer (0, 27, 54, and 81 kg ha−1), and the third was the dose of zeolite (0, 3, and 6 t ha−1). The results showed that applying zeolite minerals at all altitudes increased nutrient availability and soil cation exchange capacity (CEC) by up to 70%. The novelty of this study is that the soil from an altitude of 900 m asl, with a P2O5 fertilizer dose of 54 kg ha−1, has a loamy sand soil texture and produces the highest asiaticoside content (3.61%) and the largest plant dry weight (19.24 g). These results did not significantly differ from those obtained from the soil 450 m asl with a sandy loam soil texture (the most suitable soil texture for C. asiatica), that is 3.37% asiaticoside and 19.87 g plant dry weight. This study concluded that C. asiatica could develop in loamy sand soil by giving it 54 kg ha−1 P2O5 fertilizer.

Rice production in the karst dryland is still low, due to soil characteristics that lack nutrient availability. Meanwhile, upland rice has received less attention, and it has not been used to its full potential. This study aimed to evaluate the effect of various combinations of inorganic fertilizers, poultry manure, and upland rice varieties on the production and economic value of karst dryland in Gunungkidul, Yogyakarta. This experiment was arranged in a factorial design, with inorganic fertilizers, poultry manure, and upland rice varieties set in a randomized block design with three replications. The first factor was a combination of inorganic and organic fertilizer rates: 72 N kg ha−1 + 26 P2O5 kg ha−1 + 25 K2O ha−1 + 3 t ha−1 organic, 92 N kg ha−1 + 36 P2O5 kg ha−1 + 30 K2O kg ha−1 + 2 t ha−1 organic, 112 N kg ha−1 + 46 P2O5 kg ha−1 + 35 K2O kg ha−1 + 1 t ha−1 organic. The second factor is the upland varieties of Inpago 8, Inpago 10, and Inpago 12 and lowland variety Inpari 42 Agritan GSR, as checked. Based on the study, we concluded that the combination of 92 N kg ha−1 + 36 P2O5 kg ha−1 + 30 K2O kg ha−1 + 2 t ha−1 poultry manure fertilizers with Inpago 8 resulted in an IDR profit of 23,586,000 ha−1, and it is the most recommendable fertilizer and variety combination to be developed in the karst dryland, in consideration of land fertility and sustainability.

Tungro is one of the important diseases in rice that is still a constraint to increased productivity. Tungro disease caused by a tungro viruses that is transmitted by green leafhoppers in a semi persistent manner. The presence of weeds can cause yield losses of rice and is a potential host plant of tungro viruses. Eradication of weeds is an attempt to eliminate the source of inoculum of tungro viruses. The research objective was to determine the effect of weed eradication on the development of green leafhopper population and the incidence of tungro disease. The study was conducted in an experimental field of Tungro Disease Research Station, Lanrang Village, Sidenreng Rappang District, South Sulawesi at rainy season and dry season 2014. The experiment was arranged in a randomized complete block design with 8 eradication treatments and 4 replications. The parameters include the observation of weed species that grow in each plot and embankment planting, green leafhopper population density and the number of infected plants by tungro viruses. Observations in the planting is done at 2, 4, 6, and 8 weeks after planting (WAP). The observations of weeds and green leafhopper population was also conducted on the field before eradication. The results showed that the weeds potential as a source of inoculum were Cyperus rotundus , C. iria , Fimbristylis miliacea , and E. colonum . Eradication of weeds before and after planting through both mechanical and herbicide applications tended to suppress the green leafhopper populations and tungro disease incidence.

Jarwo super technology is a combination of superior rice farming technology, including the 2:1 paired rows planting system, high yield potential varieties, bio-decomposers, biological fertilizers, bio-pesticides, and agricultural mechanization application. The assessment aims to determine plant diversity, production increase, and financial feasibility of jarwo super technology rice farming. The assessment was conducted on March-Juni 2017 with the “demplot” method of applied jarwo super technology in Karanganyar Regency, Center of Java. Primary data is growth, production, and rice farming performance at the “demplot”, as well as existing farmer data. Samples were collected purposively, it’s the farmers who carried out the “demplot” and the farmers around the “demplot”, which meant 30 farmers. Data were descriptively analyzed using the average value, RCR, MBCR, net profit value, and BEP. The results showed that the rice yields with jarwo super was 15.63%higher than the existing farmers. Jarwo super rice farming is more efficient and economically feasible with RCR 1.44 value. MBCR is 11.6 value, it that each additional cost of implementing jarwo super rice farming of 1.000 IDR increases income by 11.600 IDR. Proportion of costs increase in jarwo super rice farming is 350.000 IDR, but profits reached 4.077.083 IDR. Net profit value of 1.7 shows that jarwo super rice farming can increase profits. Production level and dry grain harvested price on farmers level were 30.76%higher compared to BEP production and BEP price. Jarwo super rice farming is feasible to develop that because can increase farmer’s production and profits.