Journal of Tropical Crop Science
Not a member yet
315 research outputs found
Sort by
Soil Water Content Below 33.7% Progressively Reduces the Latex Yield of Rubber PB 60, A Study in Sembawa, South Sumatra, Indonesia
Get PDFRubber is one of the economically important tropical trees that produces natural rubber, an essential industrial raw material in Indonesia. In general, rubber can grow well in areas with 1,500 - 3,000 mm rainfall per year that evenly distributed round the year. During the dry season, water availability is reduced so that water becomes a limiting factor for the growth and production of the rubber tree. This paper aimed to determine minimum soil water content that must be maintained to prevent the reduction of PB 260 rubber production based on field water balance. This research was carried out at the Indonesian Rubber Research Institute Experimental Field, South Sumatra, Indonesia, between 2014 to 2019. This experiment used PB 260 clone which was planted in 2001 using a 6 x 3 m plant spacing. Soil analysis showed that the Sembawa had a clay loam soil texture. The measured parameters were latex production (kg per ha per year), rainfall, and evapotranspiration (mm). The results from our six years of study showed that rubber production always decreased when soil water content started to decline below field capacity (33.7 %, or equal to 337 mm with 1m depth of root zone)
Agronomic Performance and Selection of Doubled-Haploid Rice Lines for Rainfed Lowland Paddy Field
Get PDFRainfed lowland rice cultivation is an alternative to increase national rice production. Breeding of high yielding rice varieties suitable for rainfed lowland condition can be accelerated by using doubled-haploid (DH) as genetic materials. This study aimed at obtaining information on the agronomic performance including yields in several DH rice lines and selecting DH lines suitable for rainfed lowland paddy field. The experimental design used was a Randomized Complete Block Design with 3 replications. The treatment was thirty DH lines and 4 check varieties namely RJ31 Ciherang, RJ32 Inpari 18, RJ33 Inpari 40, and RJ43 Inpari 41. The results showed that there were variability in all agronomic performances, i.e., plant height, number of tillers, days to heading and to harvest, panicle length, number of filled and empty grains, 1000-grain weight and grain yield. The DH lines, namely RJ19 DR8-43-3-1 and RJ25 DR10-14-1-1, gave the same productivity as 4 check varieties. Index selection showed that twelve DH lines with medium number of productive tillers, early maturing, and productivity of more than 4.40 tons.ha-1 were selected for further evaluation
Optimizing Sago Land Utilization by Intercropping with Eggplants, A Study at Tanjung Peranap Village, Meranti Island, Riau, Indonesia
Get PDF Sago palms are the main food crops in eastern part of Indonesia. Sago productivity can reach 20 to 40 per ha per year, and the trees can be harvested when they are 10 years of age. Due to long duration before harvesting it is important that sago growers could grow annual food crops. The objective of study is to determine the growth of sago palm intercropped with eggplants, and how intercropping aff ects each crop grown as monoculture. The study was carried out from March to July 2018 at Tanjung Peranap Village, Meranti Island District, Riau Province, Indonesia. The experiment was organized in a completely randomized block design with two replications, with sago palm and eggplant as monoculture and as inter cropping. The results demonstrated that young sago palm did not suppress eggplant growth and vice versa. Therefore, eggplants can be planted between young sago palms
Growth, Production and Bioactive Content of Several Black Cumin (Nigella sativa L.) Accessions With Different Harvesting Times in a D3 Type Climate Regime
Get PDFBlack cumin (Nigella sativa L.) is a species Ranunculaceae family which grows in the Middle Eastern and Southern Mediterranean countries. Black cumin is also known as habbatus sauda , or kalonji in South Asia. Black cumin seeds are used as spice traditional medicine; the essential oil compound in the seeds has been identified as thymoquinone. Thymoquinone has a potent antioxidant effect, which could protect organs from oxidative damage by generating free radical agents. Indonesia is one of the most geographically diverse country in the world. Some regions have scattered low and high plains, abundant sunlight, evenly distributed rainfall throughout the year, and highly diverse soil types. The purpose of this study was to study the growth, production, thymoquinone and thymol content of several accessions of black cumin with different harvesting time in D3 type climate regimes. The research was conducted from April to September 2019 in Ngadirejo Village, Sukapura District, Probolinggo Regency, East Java with an altitude of 1.680 m above sea level. The experiment used a randomized complete block design with one factor for the vegetative phase, namely accession (“American”, “Indian”, “Kuwait”, and “Slovenian”) and two factors for the generative phase, namely accession and harvesting time. The harvesting time of black cumin was conducted at 6, 7, and 8 weeks after the anthesis. “Indian” and “Slovenian” accession demonstrated the best vegetative growth, whereas “Indian” had the highest capsules number per plant, seeds weight per plant, and the highest estimated production compared to other accessions (603 kg seeds. ha-1). “American”, “Indian” and “Kuwait” accessions are well adapted in D3 type climate. The harvesting time of 7 to 8 weeks from anthesis was shown to be optimal for all accessions. Thymoquinone and thymol content for the four accessions was circa 349.64– 3,030.45 μg. g-1 of seeds and 385.56 – 2,003.46 μg.g-1 of seeds, with potential production values of 0.18 - 1.83 kg.ha-1 and 0.19 - 0.45 kg.ha-1, respectively. The optimal harvesting time to maximize seed production was unaffected by the black cumin accession
Study of Growth and Production of Tomato Cultivars In Response to Fruit Thinning at Tamansari, Tasikmalaya, West Java, Indonesia
Get PDFTomato is a horticultural crop that is widely cultivated in Indonesia because of its multipurpose uses. The prospect of marketing tomatoes is quite promising for local, national and export markets. The demand of tomato consumption has been increasing, but has not been supported by the availability of quality and quantity production. The area for tomato production has even been decreasing, especially in West Java, Indonesia. One of the causes of the low tomato production in Indonesia is due to the unavailability of superior varieties at the farm level, and very limited information on suitable farming technology. In addition, farmers have difficulty meeting supermarket and export standards because of the mismatch of the quality required by the market and the quality of the products. Efforts that can be made to improve the quality of tomato fruits includes the use superior varieties, and to apply better management of crop production. This study aims to determine the tomato variety which is suitable and high yielding to grow in Tamansari sub-district, Tasikmalaya, West Java, Indonesia, and to understand the effects of thinning fruit on tomato production. The study was carried out from August to November 2018 in Taman Sari, Tasikmalaya City, in a completely randomized design with tomato variety and fruit thinning as the treatments. The study used three tomato cultivars, “Betavila”, “Tymoti”, “Martha”. The levels of fruit thinning tested were 15%, 25%, and without fruit thinning as control. The results demonstrated that the choice of tomato variety and fruit thinning had very significant effects on the yield component of tomato. “Marta” is one of the suitable varieties suggested to be cultivated in the area in Tasikmalaya, and fruit thinning at 25% gave the highest fruit yield
A Review of Root Pruning to Regulate Citrus Growth
Get PDFRoot is the important plant organ hiding below the soil that serves as plant supporting structure, water and nutrient supplier and assimilates storage. Root growth occurs in turn with shoot part, forming repeated cyclic pattern because of the photosynthate competition. Root growth regulation is one of the promising practices to boost the yield of fruit tree, especially citrus that is economically important and highly demanded fruit. Root pruning varied based on the scale of intensity and plant growth stage, including air root pruning, knife root pruning and modern pruning using root pruner machine mounted to a tractor. Root pruning to induce the growth of more fi brous root system and to correct root deformation at seedling stage have potentials to improve post-transplant growth. Besides, it has a potential to replace the use of chemical plant growth regulator for a more environmentally friendly practice. The pruning of root impeded the canopy growth, altered the plant water status leading to fl ower promotion. In addition, it is also a promising practice to overcome the alternate bearing on fruit tree, including citrus, through the suppressing of excessive growth and restricting the high fruit load during the ‘on year’ and allowing a better carbohydrate storage for the improvement of yield during the ‘off year’
Evaluation of Growth and Physiological Responses of Three Rice (Oryza sativa L.) Varieties to Elevated Temperatures
Get PDFTemperature is a primary factor that affects the rate of plant development and has great impacts on plant growth, metabolism, and yield. A study was conducted to analyze the effects of elevated temperature on rice morphological and the physiological growth. The research was arranged in a nested randomized block design consisting of two factors, temperatures and rice varieties. Elevated temperatures were provided through the uses of different materials of plastic roof and walls to have an average and maximum temperature of 27.6 °C and 41.6 °C (T1); 28.1°C and 43.8 °C (T2), and 29.5°C and 47.1 C (T3), respectively. The study used three varieties of rice, “Ciasem”, “Ciherang”, and “IR64”. All rice varieties showed signifi cant increases in tiller number per hill and shoot dry weight, but had a decrease in the stomatal conductance, transpiration rate, and SPAD values at grain fi lling stage with the increasing temperatures. The number of tiller per hill increased when temperature was elevated from 27.6 to 28.1 and 29.5°C by about 29.9 and 21.3%, respectively
Weed Growth and Lowland Rice Production as Affected by Planting Patterns and Rice Varieties
Get PDFWeeds are one of the most limiting factors in rice cultivation. This study aims to evaluate the eff ects of rice planting patterns on the prevalence of several weed species, Cyperus iria, Echinochloa crusgalli, Fimbristylis miliacea, Leptochloa chinensis, Ludwigia octovalvis, and Spenoclea zeylanica, and to discuss the implications on rice production systems. The research was conducted in IPB Sawah Baru experimental farm in Bogor, West Java, Indonesia, from December 2017 to April 2018. The experiment was arranged in a randomized block design with two factors, rice varieties and rice planting methods. The rice varieties, “IPB 3S” and “Ciherang”, were assigned as the main plot, whereas planting methods, i.e. 25x25 tile, Legowo 2:1 (double rows), Legowo 4:1 (quadruple rows), as sub-plots. The results showed that in the “IPB 3S” plots L. octovalvis shoot dry weight decreased by 33.0%, the root dry weight of L. chinensis roots decreased by 22.6%, and the number of S. zeylanica weed leaves decreased by 28.4% compared to the plots planted with “Ciherang”. With legowo 2:1 planting method the dry weights of L. octovalvis decreased by 21.5%, L. octovalvis by 1.7%, and L. chinensis by 4.4%, and the number of weeds E. crus-galli by 7.0 % compared to Tegel 25x25 method. L. chinensis seemed to be a dominant weed at both vegetative and generative stage of rice development
A Report on Gamma Radiation Induced Variation in Seed Characters of Cicer arietinum L.
Get PDFCicer arietinum L. (chickpea) is one of most popular and cheap source of plant protein and minerals worldwide. The present study was directed to induce variations in seed characters of chickpea “Vijay”, especially with reference to increase in its protein and mineral content using gamma radiations as mutagenic agent. M2 population of Cicer arietinum L. “Vijay” after post-harvest analysis revealed that 300 Gy dose of gamma radiations induced significant variations in seed characters including seed size, surface texture and seed coat color. Total nine mutants were identified differing from control in seed coat colors and categorized into four groups on the basis of seed size as normal, small, bold and extra bold; two groups on the basis of surface texture and wrinkled or smooth surface. The seed yield of all mutants was noted as 100-seed weight, which was corresponding with seed size. The biochemical analysis of the seed mutants in the form of protein, iron and zinc content indicates that, seeds with dark colored seed coat have higher level of protein and minerals as compare to control
Potassium Sources and Rates for Drip Irrigated Polyethylene Mulched Chilli Pepper
Get PDFFertigation with drip irrigation is one of the technologies to solve fertilization and irrigation problems in chilli pepper production using polyethylene mulch. Potassium (K) is one of the important macro nutrients that affect plant growth and development due to its roles in the biochemical and the biophysical processes in plants. The objective of this study was to determine the best sources and the optimum rates of potassium for drip irrigated polyethylene mulched chilli pepper field production. The study was conducted in January until July 2018 at Tajur Experimental Farm, Center for Tropical Horticulture Study, Bogor Agricultural University. The experimental design was a split plot with the K sources (KCl, ZK, NPK) as main plots and K rates that consisted of five levels (0, 68, 136, 204, 272 kg K2O. ha-1) as sub-plots. The results showed that the best optimum rate of K to produce fruit is 101.11 kg K2O.ha-1 with a maximum yield of 2.26 t.ha-1. Chilli crops fertilized with NPK and KCl had the greatest fruit weight per plant, fruit weight per plot, and fruit weight per hectare