Journal of Tropical Crop Science
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Optimization of Nitrogen Fertilization and Seedling Density of A New Rice Type (Oryza sativa L.) “IPB 3S”
Get PDFThe new plant type of rice, or ‘padi tipe baru’ (PTB) in Indonesian, is a new group of rice cultivars with a higher productivity compared to the modern rice varieties (‘varietas unggul baru’ or VUB). This study was conducted to determine the optimum dose of nitrogen fertilization and the seedling density or number of seedlings per hill to increase growth and yield of the new type of rice “IPB 3”. The experiment was conducted in the Bogor Experimental Station in January to June 2015. Nitrogen doses (90, 120, 150, 180 kg N.ha-1) and number of seeds per hill (1, 5, 10, 15 and 20) were tested. The results showed that the increased dose of nitrogen fertilizer reduced the percentage of filled grains, the rate of photosynthesis and the grain yield per hectare. Similarly, an increase in the seedling density up to 15 seeds decreased the dry matter of the crop, the number of grains per panicle, and grain weight per plant, but increased the grain yield per hectare. The optimum yield of “IPB 3S” was achieved with 90 kg N.ha-1 with 15 seeds per hill. The results of this study have provided a guideline for an improved nitrogen management in relation to rice seedling population to increase yield of a new rice type “IPB3S”.Keywords: “IPB 3S”, new plant type, fertilizer, local variet
Radiosensitivity Levels of In Vitro Cultured Celosia cristata Planlets by γ - Ray Irradiation
Get PDFPlantlets of the ornamental plant Celosia cristata were irradiated with gamma rays to increase their genetic diversity. This study was aimed to establish the lethal levels of gamma radiation (LD20, LD30 and LD50) for C. cristata plantlets. The irradiation doses used were 0, 25, 50 and 75 Gy. The growth of irradiated plantlets was evaluated to the third generation. Irradiated C. cristata MV1 plantlets showed a decrease in growth, with plantlets irradiated at 75 Gy showing only 30% survival. Abnormal growth characteristics observed in the third generation plantlets included the shortening of internodes, and curling of leaves. LD50, LD30 and LD20 of C. cristata were 68.73 Gy, 46.68 Gy and 35.65 Gy, respectively
Controlling Poinsettia (Euphorbia pulcherrima Will.) Height with Growth Retardant Application in West Java, Indonesia
Get PDFA study was conducted to evaluate the effects of the growth retardant Cycocel application in the growth and development of poinsettia (Euphorbia pulcherrima) ‘Freedom Red’. Cycocel was applied by spraying plant shoots at the concentrations of 1000, 1500, 2000, 2500 ppm. The increase in cycocel concentrations reduced plant height, leaf size, internodal length, plant spread and the number of flowering plants. All cycocel concentrations resulted in an ideal potted plant height. The optimum spray concentration of Cycocel used to obtain compact and uniformly flowering plants under tropical West Java environment was 1000 ppm
Characterization of 13 Accessions of Purslane (Portulaca sp.) from Bogor, West Java, Indonesia
Get PDFCharacterization is part of crop the breeding process aims to protect biodiversity and preserve local germplasm. Indonesia has two known species of Portulaca, Portulaca oleracea and P. grandiflora. Thirteen Portulaca accessions have been collected from Bogor area, comprising five accessions of Portulaca oleracea and eight accessions of Portulaca grandiflora. This study was aimed at the characterization of the 13 accessions and was undertaken at Indoflower BLST, Bogor, between October 2015 to February 2016. The results showed a significant difference in the color of flowers between the two species of Portulaca. The most significant difference is the overall appearance of P. oleracea species. Character color and shape of the flowers between the P. grandiflora white (GW) and P. oleracea are similar. Significant differences between the species exist in relation to the root systems, but the root systems of accessions within each species are generally similar. The branching characteristics between the two species and among accessions are generally similar, with branches emerging through the base of leaves or nodes. However, there are differences in the leaf characteristics between the two species. This study has provided information on flower characteristics of P. grandiflora and P. oleraceae which will be valuable for future breeding efforts in Portulaca.
Effect of Various Levels of NPK Fertilizer on the Yield Attributes of Soybean (Glycine max L.) Varieties
Get PDFIndonesian soybean production can only meet about 30% of national demand. Efforts to increase soybean production include the use of improved seed quality and fertilizer application. The aims of this research were to 1) examine the responses of six genotype soybeans to the application of different doses of NPK fertilizer; 2) determine the seed protein content of the six soybean genotypes following NPK application; 3) determine the interaction between soybean genotypes with NPK doses in affecting growth and yield. This research was conducted under a plastic house at the Faculty of Agriculture, University of Jenderal Soedirman, Central Java, Indonesia. The experiment was arranged in a randomized block design with three replications using six soybean varieties and four levels NPK fertilizer. Soybean varieties tested were “L/S: B6-G1” (V1), “L/S:B6-G3” (V2), “L/S:B6-G4” (V3), “Grobogan” (V4), “Burangrang” (V5), and “Argomulyo” (V6). Four levels NPK fertilizer tested were: without fertilizer (N0), 0.6 g per plant (N1) 1.2 g per plant (N2), and 18.g per plant (N3), or 0, 100, 200 and 300 kg.ha-1. “L/S: B6-G1” had the greatest number of seeds per plant (184) following treatment with 300 kg.ha-1 of NPK. The seed protein content increased with the increase doses of NPK. “Argomulyo” treated with NPK at 300 kg.ha-1 had the highest seed protein content (34.5%). Soybean responses to NPK treatment differed with varieties, particularly in the number of fl owers per plant, number of seeds per plant, grain weight per plant and seed protein levels
Proliferation of Protocorm-Like Bodies of Dendrobium mannii and Dendrobium mirbelianum in Chitosan-containing Media In Vitro
No full textDendrobium mannii and Dendrobium mirbelianum were rare and endangered orchid species. In vitro micro propagation could be used to conserve and proliferate these species. The aims of this study were to determine the effects of chitosan on proliferation of the protocorm-like-bodies (PLBs) of in vitro grown Dendrobium mannii and D. mirbelianum. Chitosan has been reported as an important component to promote orchid growth in vitro. In this study chitosan was included in the in-vitro media at the concentrations of 0, 1, 2, 3, and 4 mg.L-1. The highest PLBs formation, clump diameter, and fresh weight on D. mannii were obtained from explants cultured on medium supplemented with 1 mg.L-1 chitosan. After 14 weeks of culture, fresh weight, clump diameter and average number of PLBs of D.mannii were 29.52 %, 33.00 % and 35.88% greater at chitosan (1 mg.L-1) compared to control media. D. mirbelianum treated with low chitosan concentrations (1 and 2 mg.L-1) had 65.71% more leaves than those without chitosan treatment. Chitosan, however, had an adverse effects on growth of both species at 4 mg.L-1. Medium contain 4 mg.L-1 chitosan induced PLBs proliferation of D.mannii, but inhibited PLBs proliferation of D.mirbelianum. These results suggested that chitosan had important roles in PLB proliferation and could be used for the propagation of D. mannii PLBs in vitro. Keywords: rare orchid species, in-vitr
Water Balance in Oil Palm Plantation with Ridge Terrace and Nephrolepis biserrata as Cover Crop
Get PDFThe existence of oil palm plantations as a possible cause of drought in the surrounding areas in Indonesia is a critical issue. Therefore, information related to the effects of oil palm plantations on the surrounding environment in terms of soil water content (SWC) availability is needed. Soil and water conservation techniques in the form of ridge terracing and cover crops, such as Nephrolepis biserrata, can be expected to potentially improve soil water reserves, especially in the dry-season, by accumulating water in the rainy season. This study aimed to study the effects of N. biserrata as cover crop, together with the potential effects of ridge terraces, on the water balance in mature oil palm plantations. The research was conducted in mature oil palm plantations, Afdeling III block 375 (planted in 1996) and block 415 (planted in 2005), Rejosari Unit, PT Perkebunan Nusantara (PTPN) VII in Natar District, South Lampung Regency, Indonesia, from August 2014 to January 2015. The research was based on of setting up 15 m x 20 m experimental plots with the following treatments: (i) without ridge terraces and without N. biserrata (G0T0); (ii) without ridge terraces but with N. biserrata (G0T1); (iii) with ridge terraces but without N. biserrata (G1T0); (iv) with ridge terraces and with N. biserrata (G1T1). Hydrology parameter data were collected for each treatment plot; water balance was calculated using a water balance equation. The results showed that the use of the cover crop N. biserrata in combination with ridge terraces helped improving SWC reserves by approximately 71% and 12%, respectively. The use of N. biserrata as a cover crop reduced the rate of water loss by percolation and run-off, by approximately 36% and 80%, respectively, in an area where the annual rainfall is above 2,400 mm per year. The presence of N. biserrata shortened the period of SWC deficit by extending the period of a water surplus by 70 days when compared with ridge terracing alone (which reduced the period of SWC by 50 days)
Soil Fertility Assessment of Sugarcane Farms in Barangay Aglayan, Malaybalay, Bukidnon, Philippines
Get PDFA soil fertility assessment survey was conducted at Barangay Aglayan, Malaybalay, Bukidnon, Philippines, on selected farms to assess the soil chemical properties (pH, OM, Extractable P and Exchangeable K) of sugarcane farms. A survey questionnaire was used to gather information among farms and a total of twenty-two (22) sugarcane farms were collected for soil samples and analyzed at the Soil and Plant Analysis Laboratory, College of Agriculture, Central Mindanao University. The 22 sugarcane farms surveyed in of Barangay Aglayan, Malaybalay, Bukidnon were identified as very strongly acidic, have medium organic matter content, low extractable phosphorus and very low in exchangeable potassium. These results demonstrated that the sugarcane farms in Bukidnon need amendments to meet the recommended soil test values for sugarcane. The results of this study have provided basic information to generate a soil nutrient map of sugarcane farms in Bukidnon, Philippines
Evaluation of Leaf Spot Resistance and Agronomic Characteristics of Groundnut Advanced Breeding Lines
Get PDFLeaf spot is a major groundnut disease in Indonesia and worldwidewhich has the potential to cause a yield loss of up to 60%. The use of leaf spot resistant cultivars is an easy, economical, and environmentally friendly way in groundnut cultivation to maintain high yields. The objective of the research was to evaluate the yields of 16 groundnut lines which had been developed to be leaf spot resistant and high yielding. The research was conducted in 2010 – 2011 at the Bogor Agricultural University (IPB) experimental station in Cikarawang, Indonesia. A randomized complete block design with three replications was used in the experiment. The groundnut lines evaluated were crosses between “Gajah”, a cultivar which is known to be susceptible to leaf spot, and the resistant line GPNC- WS4. Four Indonesian cultivars “Gajah”, “Jerapah”, “Zebra” and “Sima” were used as control. The results showed that selected lines demonstrated better resistance to leaf spot compared to “Gajah”. Their agronomic characteristics, such as pod number, filled pod number, pod weight, and kernel weight, were not significantly different from the control cultivars. The results of this study have provided information on groundnut leaf spot resistant lines for further evaluation
Fruit Coating with Chitosan and Beeswax to Increase Papaya Shelf Life
Get PDFPapaya (Carica papaya) is a climacteric fruit with an increased respiration rate during ripening process. Papaya respiration rate can be inhibited by providing a coating on the surface of the fruits, including chitosan, a polysaccharide derived from shrimp shell waste, or beeswax.The purpose of this research was to examine the effects of chitosan and beeswax coating on the shelf life and quality of papaya Callina fruit during storage. Results of the experiments showed that fruit coating with chitosan and beeswax can extend the shelf life of papaya Callina by four to five days compared to control due to inhibition respiration rate of papaya fruits during storage.The use of chitosan and beeswax was beneficial to maintain the physical and chemical quality of papaya Callina fruits