Journal of Tropical Crop Science
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The Effects of Preharvest Mild Shading on the Quality and Production of Essential Oil from Kaffir Lime Leaves (Citrus hystrix)
Get PDFKaffir lime (Citrus hystrix DC) is a less popular citrus species commonly used as a food spice and a source of essential oil. Early studies report the success of preharvest mild shading to increase leaf yield, although there is still limited information on the effect of preharvest shading on the quality of essential oil produced. The aim of this current study is to evaluate the effect of preharvest mild shading factors on the yield, physical characteristics, and metabolite fingerprinting of kaffir lime leaves essential oil (KLLEO). One-year-old kaffir lime trees were sampled in two preharvest treatments, i.e., open sun and mild shading (24% light reduction) at Pasir Kuda experimental field, Bogor, Indonesia. Statistical analysis showed that there was no significant effect of preharvest treatment on yield and physical characteristics (color, specific gravity, and refractive index) of KLLEO. In contrast, there was a metabolite fingerprinting variation of KLLEO as an effect of mild shading. The relative percentage of bergamol, citronellol, caryophyllene oxide, citronellic acid, isopulegol, isopulegyl formate, limonene, linalool, and linalool oxide was increased by mild shading. On the other hand, the main metabolite (citronellal) was significantly reduced by about 10% in shading treatment, as compared to the open-sun ones
Investigation of Vibration Technique To Control Physical Properties of Yam Tubers (Dioscorea rotundata Poir) uring Storage
No full textYam tubers lose weight during storage and prolonged storage can reduce tuber quality and quantity. This study investigated the application of vibration techniques for the control of the physical properties of yam tubers during storage. Measurements were conducted on the physical properties of the tubers: weight loss, shrinkage of the middle diameter, shrinkage of the length, top and bottom diameter, on 108 tubers treated and 32 tubers untreated (control). The factors of the experimental design were three levels of vibration frequencies, i.e. low (1 – 5 Hz), medium (60 – 100 Hz) and high (150 – 200 Hz), amplitudes of low (5 mm), medium (10 mm) and high (20 mm), and durations of low (5 minutes), medium (10 minutes) and high (15 minutes). Tuber weights were classified as small (0.1 – 2.9 kg) and large (3.0 – 5.0 kg). The tubers were stored for ten weeks after vibration, and their physical properties were measured every week during the storage period. Our study demonstrated that as the frequency, amplitude, and duration of vibration increase, the physical properties of yam tubers decrease significantly in both tuber classes. The study shows that mechanical vibration can slow down the changes in the physical properties of the yam tuber during storage
Invigoration Increased Quality and Storability of True Seed of Shallot (Allium ascalonicum L.)
No full textSeed invigoration is a pre-planting seed treatment by balancing the seed water potential and stimulating their metabolic activities so that the seeds germinate simultaneously. In this study, invigoration treatments were applied to improve the quality of the true seeds of shallots (TSS) that had started to deteriorate. Invigoration increases the moisture content of the seeds so the seeds need to be re-dried to extend their storability. The aims of the study were to determine the best invigoration treatment and the drying method to maintain the benefit of invigoration, and to prolong TSS storability after invigoration and drying. This research was conducted at the Laboratory of Seed Quality Testing, IPB University, Indonesia, and consisted of three experiments, i.e., invigoration of deteriorating TSS to improve their viability and vigor, drying after invigoration to extend seed storability, and seed storability after invigoration and drying treatments. The first experiment was arranged in completely randomized design with one-factor (invigoration solutions), i.e. control, medium containing 3% KNO3, 50 ppm GA3, 0.5 % ZnSO4 or PEG6000 -10 bar. The second experiment was conducted using a two-factor completely randomized design, drying temperature (20˚C, 30˚C, and 40˚C), and drying duration (8 hours, 16 hours, 32 hours, and 48 hours). The third experiment was arranged in a nested design with two factors. The first factor was a seed storage condition, i.e., ambient temperature, air-conditioned room, and refrigerator. The second factor was seed packages, i.e., aluminum foil and polypropylene plastic. Non-invigorated seeds were used as control. The studies were conducted on two shallot varieties separately, “Trisula” and “Lokananta”, except in the third experiment which only used “Lokananta”. The results showed that invigoration in 3 % KNO3 and 50 ppm GA3 effectively improved the vigor of deteriorating TSS. Drying the seeds at 40˚C for 8 hours was the most effective method to reduce seed moisture content without reducing the benefit of invigoration. Storing the invigorated TSS in an air-conditioned room with aluminum foil packaging, or in a refrigerator with aluminum foil or plastic packaging until 14 weeks maintained the benefit of invigoration. The quality of the invigorated TSS was maintained until 14 weeks in an air-conditioned room with aluminum foil packaging, or in a refrigerator with aluminu
Effect of Rates and Sources of N Fertilizer Application on Dynamics of Rice Brown Leaf Spot Disease (Bipolaris oryzae) Incidences in the Dry Zone of Sri Lanka
Get PDFNitrogen inputs; sources or application amounts are key determinants of yield determination and determination of resistance or sensitivity to pathogen activities. This study aimed at assessing the impact of source and rate of application of N fertilizers on Rice Brown Leaf Spot (RBLS) disease incidences and dynamics in lowland irrigated rice crops. Leaf N using relative leaf chlorophyll content, leaf N concentration and crop yield were assessed during the wet 2018/19, 2019/20 and 2020/21 seasons and dry 2019 and 2020 seasons in the field research facility of Rajarata University of Sri Lanka. The conventional systems (The Department of Agriculture recommended inorganic fertilizer application at 100% N), integrated system (50% N with conventional through inorganic fertilizer and 25% N with organic manure mixture), and organic system (50% of N conventional through organic manure) were tested using a new improved rice variety Bg300, using a randomized complete block design with six replicates. Wet and dry seasons were contrastingly different in disease prevalence, where critical levels of incidences were visible earlier in the wet season compared to the dry season. Initial stages of the study, organic systems resulted in higher disease incidences, thus reaching infections of the full crop before conventional and integrated. Several seasons of continuous organic manure incorporation enhanced the resistance of organic systems to RBLS disease compared to the rest. The leaf N concentrations were higher in conventional, thus the RBLS incidences were relatively low, due to negative correlations between disease incidences. Rice yields also resulted in a significant negative correlation with disease incidences and were diminished in integrated and organic systems later. The yield suppression due to diseases such as RBLS in organic transition can be overcome by using an integrated approach and building a balanced substitutable nutrient management strategy
Evaluation of Rapeseed-mustard Genotypes in Different Sowing Regimes and Their Genetic Variabilities
No full textRapeseed-mustard is an important oilseed species with high nutritional and economic values; it’s popularity increases due to its diverse uses. Ten genotypes of rapeseed-mustard and two sowing dates were evaluated in a split plot design with three replications. Our study demonstrated that sowing dates and genotypes greatly influenced the growth parameters, yield, and it contributing characters. BARI sarisha-16 had the highest yield (1613 kg.ha-1) whereas Binasarisha-9 yielded the lowest yield (840 kg.ha-1). All the yield contributing characters was superior in the earlier (10 November, S1) sowing date than the 24 November (S2), demonstrated by the highest grain yield (1120 kg.ha-1) which was 10 % higher than the seed sown on 24th November (S2) (1025 kg.ha-1), and better higher vegetative growth. These results affirmed that the yield contributing traits resulted the higher seed yield. In most of the studied characters, the higher phenotypic variances were observed than that of its genotypic variances. The significant positive correlation with grain yield were found in plant height, number of primary branches/plants, number of siliqua/plants, siliquae length, number of seed per siliquae, days of 50% flowering to maturity and 1000 seed weight. Therefore, based on the yield and the related traits, BARI sarisha-16 can be used for further utilization
Agronomic Performance of IPB’s Red Chili Pepper (Capsicum annuum L.) Lines in Different Environments in Bogor, West Java, Indonesia
Get PDFOur study aims to determine the agronomic performances of the red chili pepper genotypes developed by the IPB University as compared to the existing commercial varieties. The study was conducted from June 2019 to April 2020 in the Leuwikopo and Tajur experimental fields, IPB University, Bogor, West Java, Indonesia. Leuwikopo and Tajur location differs in the soil type and environments. The experiments at Leuwikopo were conducted twice, once during the dry season, and once during the rainy season. The experiments were set up in a completely randomized block design with a single factor, i.e. sixteen red chili pepper lines, replicated three times in three different environments. The 11 lines evaluated were F8120005-141-16-35-1-3, F8120005-141-16-35-1-4, F8120005-141-16-35-7-1, F8120005-241-2-9-4- 4, F7120005-120-7-1-7-8-1-2, F6074-7-4-2-1, F4074136-2-3, F474077-1, F474035-2-1, F474035-2, F4136074-1-4; these lines were compared to five commercial chili varieties, “Laris”, “Gada” F1, “Kastilo” F1, “Anies IPB”, “Seloka IPB”. Measurements were conducted on time to harvest, fruit length, fruit diameter, weight per fruit, number of fruits per plant, fruit weight per plant, and productivity. The results showed that the curly and large red chili pepper genotypes had similar agronomic performances to the control curly variety “Laris” and “Kastilo” F1, and and “Anies IPB”, “Seloka IPB”, or “Gada” F1 as control variety for the large chili. Our study demonstrated that all large and curly red chili pepper lines developed in IPB University have excellent potentials to be commercialized into superior varieties
Development of Rapid Vigor Test Using Urine Sugar Analysis Paper for Soybean (Glycine max L.) Seeds
Get PDFSeed vigor is an essential parameter of seed quality. It plays a critical value in the decision-making for the seeds to be used in agronomic and horticultural crops. The urinary sugar analysis paper (USAP) test determines seed vigor based on leakage concentration from the seed and corresponding color change of the USAP, which are obtained after soaking the seeds in water. This research was conducted from January 2021 to November 2021, intending to develop a rapid soybean vigor test using USAP, and it was composed of two experiments. Soybean seeds of the Biosoy1 variety were obtained from ICABIOGRAD (Indonesian Center for Agricultural Biotechnology and Genetic Resource Research and Development). The seeds consisted of three different levels of seed lots (low, medium, and high viability with 35%, 64%, and 94% germination percentages, respectively). The first experiment was to determine moisture content and soaking period for the USAP seed vigor test. It was arranged in a completely randomized design with one factor as the combination of three seed lots, two levels of seed moisture content (10-12% and 13-14%), and four levels of the soaking period (0, 6, 8, and 10 hours). The second experiment was the optimization of the soaking period by seed number. It was arranged in a completely randomized design with one factor, which was combinations of three seed lots, three levels of seed numbers (50, 75, and 100 seeds), and the soaking period (four levels as 0, 6, 8, and 10 hours). The data were analyzed statistically by the Minitab package. The result showed that both combinations of 10-12% and 13-14% moisture content with the soaking period of 10 hours effectively differentiated the three seed lots into three vigor levels using USAP. Experiment 2 optimized the soaking period from 10 hours to 8 hours by using 100 seeds. The USAP color change was effectively significant to indicate seed lot vigor levels, mainly based on protein leakage concentration on USAP. The color changes from pale yellow-green for higher vigor seed lot to light greenish-blue for low vigor. The USAP was effective for the soybean vigor test for the seed lot with 10-14% moisture content by soaking 100 seeds into 50 ml of distilled water for 8 hours. The USAP is a promising rapid vigor test method but still needs to be developed further
Fruit Quality of Guava (Psidium guajava ‘Kristal’) under Different Fruit Bagging Treatments and Altitudes of Growing Location
Get PDFFruit quality is an important aspect that requires attention and more study when it comes to commercializing tropical fruits, including guava ‘Kristal’. This study aimed to evaluate the effect of bagging treatment and altitude of growing orchard on fruit quality of guava (Psidium guajava var. ‘Kristal’). This study was conducted at two local orchards managed by small-scale farmers, at Gunung Batu (1000 meters above sea level, m asl) and Brajaselebah (25 m asl), Lampung Province, Indonesia. A nested design was applied to test 5 types of bagging treatments and 2 levels of land altitude. Fruit quality was assessed by measuring both physical and chemical characteristics. Fruit size indicated by fruit weight and diameter was significantly larger in lowland compared to highland. The total soluble solids (TSS) were significantly higher in the lowland compared to the highland, while titratable acid (TA) showed an opposite result. Vitamin C of the fruits varied from140 to 146 mg per 100 g. Different types of fruit bagging and land altitudes did not affect the physical and chemical characteristics of “Kristal” guava fruits. Fruit scar intensity was higher in lowland, especially in fruit without bagging. Fruit bagging is highly recommended for farmers due to the success of this treatment to reduce fruit scar intensity, thus resulting in good fruit quality, irrespective of the growing locations
Screening of Onion (Allium cepa L.) Genotypes for Acid Tolerance Based on Morpho-physiological and Yield Associated Traits
Get PDFOnion is one of the most valuable vegetable crops grown all over the world, but its production is severely affected by abiotic stresses like drought, waterlogging, and the acidic nature of the soil. An experiment was conducted to study the morphological and yield contributing characters of four onion genotypes (Indian Onion-1, Indian Onion-2, Indian Onion-3, and Local onion) in the acidic soil condition at Sylhet region, Bangladesh. The experiment was laid out in a randomized complete block design with three replications. Results showed that four genotypes of onion differed significantly for all the morphological and yield characters. The total yield was positively correlated with plant height, bulb fresh weight, bulb diameter, bulb length, leaf sheath fresh weight, leaf sheath dry weight, root fresh and dry weight. Considering yield and yield attributing traits, Indian Onion-2 performed better in acidic soil and had the highest in bulb fresh weight (72.60 g), total yield (1.78 t.ha-1), and moisture content, followed by Indian Onion-3. Therefore, Indian Onion-2 can be selected as the best genotype for acidic soil in the Sylhet region, Bangladesh
Metabolic Profiling of Three Species of Amorphophallus (Araceae)
Get PDFA study was conducted to determine the metabolic contents of corms of three species of Amorphophallus, A. muelleri, A. paeoniifolius, and A. variabilis using gas chromatography mass spectrometry (GCMS) with water as polar solvent. The corms were collected from plants cultivated at the Leuwikopo Experimental Station, IPB University, Darmaga, Bogor, Indonesia. Metabolic profiling conducted at the Jakarta Regional Health Laboratory, Indonesian Ministry of Health, demonstrated that the three species of Amorphophallus vary in metabolic content, specifically for 12 compounds belonging to antioxidants, vitamins, saturated fatty acids, polyunsaturated fatty acids, phytosterol, alcohol, aldehyde, and alkane. Our study had shown that metabolic profiling is a potentially useful method of differentiating or determining species markers that in turn could be efficient way for genetic conservation and development of future food source