Assessment of the early growth of agarwood (Aquilaria crassna) seedlings under different sources of nutrients

The effect of different sources of nutrients on the growth of Aquilaria crassna seedlings was assessed by raising seedlings in polybags treated with inorganic fertilizer (IF), organic fertilizer (OF) and biofertilizer (BF) either alone or in combinations. The pots were established following a completely randomized block design with eight treatments: (T1) soil without IF, OF or BF ‒ control; (T2) soil + IF; (T3) soil + OF; (T4) soil + BF; (T5) soil + IF + OF; (T6) soil + IF + BF; (T7) soil + OF + BF; (T8) soil + IF + OF + BF each replicated five times. Plant height, stem diameter, dry weight of shoots and roots, leaf area and chlorophyll index were measured six months after planting. Soil pH (H₂O) and available soil P content were measured as soil parameters. The best growth performances (54.30 cm, 6.48 mm, 7.10 and 5.92 g·plant^–1, 435.33 cm² and 58 for plant height, stem diameter, shoot and root dry weight, leaf area and chlorophyll index, respectively) were recorded in T8, which also resulted in the highest available P content (18.96 mg·kg–1 soil). The lowest soil pH (H₂O) value (6.02) was recorded in T7 followed by T6 (6.17). The application of IF, OF and BF as a combination could be recommended to promote the growth of Aquilaria seedlings.

Effect of mycorrhizal provision and watering frequency on productivity and fresh material of forage sorghum (Sorghum bicolor (L.) Moench)

Sorghum is a cereal crop that has the potential to be developed as animal feed. Sorghum plant experiencing drought stress will decrease their productivity. Efforts to overcome this problem are by adding mycorrhizae. Mycorrhizae increase the ability of plants to adapt to the environment in the form of absorption of water and nutrients. This study aimed to determine the productivity of sorghum (plant height increase, plant length increase, number of leaves and stem diameter) and fresh weight of sorghum plant. The research treatments were mycorrhizal levels and watering frequency using a completely randomized design with a 3x3 factorial pattern. The mycorrhizal fungi provision consisted of three levels, namely without mycorrhizal (M0), mycorrhizal 10 g/polybag (M10), and mycorrhizal 20 g/polybag (M20). The frequency of watering consisted of watering everyday (A1), watering every four days (A4), and watering every eight days (A8). The provision of mycorrhizae significantly affected the productivity of sorghum and fresh weight of sorghum (p<0.05). The difference in watering frequency affected the increase in sorghum plant height (p<0.05). However, it did not significantly affect the increase in length, stem diameter, number of leaves, and fresh weight of sorghum. In conclusion, mycorrhizae can significantly improved the productivity of sorghum plants developed in areas with high drought levels.

Nursery performance of potentially promising rootstocks for citriculture in the south of Brazil

ABSTRACT: Diversification of rootstock varieties, with consequent reduction in phytosanitary risks, has great importance to the sustainability of citrus cultivation in the south of Brazil. This study evaluated the performance of 42 rootstocks in the nursery phase to generate ‘Valencia Late’ sweet orange seedlings. Therefore, nucellar seedlings from the rootstocks under study were analyzed in relation to plant height, stem diameter, mortality rate and percentage of bud set after grafting. The experimental design was completely randomized with four replications of 20 sample units. Not adapted genotypes had high mortality rates, and the ones of both hybrids LCR x CTSW - 009 and LVK x LCR - 038 were 100% and 90%, respectively. Other 13 genotypes had mortality rates above 30%, and ‘Sunki’ mandarin was the female genitor of ten of them. ‘Swingle’ citrumelo was the rootstock with the highest development (plant height and stem diameter), associated with low mortality rate. In relation to the other rootstocks, the best results were the fast grafting diameter, associated with low mortality rate obtained by hybrids HTR - 053, LRF x (LCR x TR) - 005, CLEO x TRBN - 245, CLEO x TRSW - 287, and citrandarins ‘Indio’, ‘Riverside’ and ‘San Diego’, as well as Trifoliate orange and ‘Rangpur’ lime. In addition to Trifoliate orange, which is widely used in Rio Grande do Sul, these rootstocks have great potential in citriculture in the south of Brazil.

Seleksi Mutan Tanaman Lamtoro (Leucaena leucocephala cv. Tarramba) Tahan Kutu Loncat terhadap Lingkungan Kering pada Rumah Kaca

Forage is the main source of feed for ruminants. Forage consists of two types, namely grass and legumes. Leguminosa is a type of forage as a source of protein. One type of legume that is well known by breeders in Indonesia is lamtoro (Leucaena leucocephala cv. Tarramba). This study was aimed to produce candidate mutants of lamtoro drought resistant to acid stress conditions. The experiment in this study used an unbalanced completely randomized design with 6 treatments of 740 different replications based on different sources of lamtoro plant mutants at different levels (P0: 0 n= 89, P1: 100 gy n= 82, P2: 200 gy n= 153, P3:300 gy n=120, P4: 400 gy n= 244, P5: 500 gy n= 52). Variables observed included plant height, number of stalks, leaf loss and stem diameter. The results showed that lamtoro plants irradiated with gamma rays at a level of 200 gy-500 gy were significantly higher than 100 gy irradiation at 10 and 12 days watering, but the diameter of the plants was larger at 100 gy irradiation. It can be watering intervals of 10 days and 12 days on the parameters of height and stem diameter showed that gamma rays irradiation of 400 gy resulted in dry-resistant lamtoro mutant candidates under acid stress condition. Key words: gamma rays, lamtoro mutant, watering interval

Growth and Genetic Parameters of Mindi (Melia azedarach Linn.) Progeny Test in Parungpanjang Forest Research Station, Bogor

Mindi (Melia azedarach Linn., family Meliaceae) is a multipurpose forest tree species such as for furniture, vinier and plywood, otherwise the leaves for pesticide and medicine material. Mindi mostly cultivated in a community forest, especially in West Java. This study was aimed to assess the growth performance and genetic parameter of the progeny test of mindi at Parungpanjang Forest Research Station, Bogor, West Java. The progeny test was established by using a randomized complete block design, consisting of 6 blocks and 73 families and each family consisting of 4 trees row-plot. The survival at 7 years old was 57.48%, height was 7.15 m and diameter is 8.59 cm, in average. The height and diameter growths among families showed a significantly different. The best family growth in height and diameter were Sumedang-31 and Bogor-18 families, respectively.The individual and family heritabilities for both stem diameter and tree heght characters were stil relatively low, with the higher family heritability value than individual heritability. The genetic correlation between total height and stem diameter of 0.57 indicates a strong correlation between the traits.

THE EFFECTIVENESS OF THE FORM AND METHOD OF GIVING SOLID ORGANIC FERTILIZER TO THE GROWTH AND YIELD OF SWEET CORN (Zea mays saccharata Sturt) IN INCEPTISOLS

This study aims to obtain a combination of organic fertilizers and the method of giving solid organic fertilizer to the growth and yield of sweet corn. The research was conducted from March to May 2019 in Karang Dapo Village, Bingin Kuning District, Lebong Regency, Bengkulu Province. This study used a Complete Randomized Block Design (RCBD) with one factor and three replications, consisting of 11 combinations namely control, solid organic fertilizer (SOF) dose of 2,5 tons ha-1 by localized placement, 5 tons ha-1 by localized placement, Petroganic 500 kg ha-1 by localized placement, Petroganic 1000 kg ha-1 by localized placement, Petroganic 2000 kg ha-1 by localized placement, SOF 2,5 tons ha-1 by side dressing SOF 5 tons ha-1 by side dressing, Petroganic 500 kg ha-1 by side dressing, Petroganic by 1000 kg ha-1 by side dressing, Petroganic 2000 kg ha-1 by side dressing. There were 11 treatment combinations, each treatment was replicated 3 times, so that 33 experimental units were obtained. The results showed that the distribution of SOF 5 tons ha-1 by localized placement had an effect on stem diameter which gave of 3.25 cm, the number of leaves 13.1 strands, and percentage of cob worth selling 100%. Giving SOF 5 tons ha-1 by localized placement giving yields reached 34.4 tons ha-1. Giving organic fertilizer gives better results than without applying organic fertilizer to all observed variables.Keyword: Solid Organic Fertilizer, Petroganic, Sweet corn, localized placement, side dressing

Reducing the Halotolerance Gap between Sensitive and Resistant Tomato by Spraying Melatonin

Salt stress is one of the primary abiotic stresses that negatively affects agricultural production. Melatonin, as a useful hormone in plants, has been shown to play positive roles in crop improvement to abiotic stress conditions. However, it remains unclear whether spraying melatonin could reduce the halotolerance gap between tomato genotypes with different salt sensitivities. Here, plant growth, H2O2 content, electrolyte leakage, antioxidant system, gas exchange, pigment content, and chloroplast ultrastructure of salt sensitive genotype (SG) and resistant genotype (RG) at CK (control), M (spraying melatonin), S (salt), and SM (spraying melatonin under salt stress) were investigated. The results showed that the weight, height, and stem diameter of the plant at SM from both genotypes significantly increased compared with S. The plant undergoing SM from both genotypes showed significantly decreased H2O2 but increased activity of SOD, APX, GR, and GSH, as well as net photosynthetic rate and Fv/Fm, as compared with S. The ratio between SM and S (SM/S) of SG was significantly higher than that of RG in terms of plant height and stem diameter, whereas antioxidant parameters, H2O2 content, and electrolyte leakage showed no difference between RG and SG in SM/S. The SM/S of SG in terms of photosynthetic parameters and pigment content were significantly higher than that of RG. Chloroplast ultrastructure showed remarkable changes under salt stress, whereas spraying melatonin reduced the destruction of chloroplasts, especially for SG. We concluded that spraying melatonin reduces the halotolerance gap between SG and RG by photosynthesis regulation instead of the antioxidant mechanism. This indicated that the positive roles of melatonin on tomato plants at salt stress depend on the genotype sensitivity.

Effectiveness of Gandasil D Fertilizer Concentration on Indigofera Seedling Growth in Various Growing Media Compositions

Indigofera sp. is an environmentally friendly source of indigo dye for batik production and a material for livestock industry because this plant potentially serves as a forage protein source. This plant has the potential to be further developed and its cultivation requires quality seeds. Seedling growth is an important factor in achieving maximum productivity. Increasing its growth can be done by providing sufficient nutrients and using appropriate growing media. The results showed that there was an interaction between the concentration of Gandasil D fertilizer and growing media composition, namely at Gandasil D fertilizer concentration of 2 g/1 liter of water and a growing medium consisting of coco peat and compost with the parameters of plant height and stem diameter observed at 10 WAP. The Gandasil D fertilizer concentration of 2 g/1 liter of water affected the growth of Indigofera seedlings more effectively than other concentrations. A growing medium consisting of coco peat and compost with a ratio of 1:1 was more effective in boosting the growth of Indigofera seedlings than growing media consisting of other compositions.

Effects of Planting Density and Weeding Frequency on the Corn Growth and Yield in Intercropping System with Peanut

The research aimed to determine the optimal population ratio at each frequency of weeding for the growth and yield of maize. It was carried out from February to May 2020 in the field. There are 2 treatment factors tested arranged in a splite plot design, which was repeated 3 times using a completely randomized block design (CRBD). The first factor is the frequency of weeding as the main plot (Main Plot) consisting of no weeding, 1 x weeding (21 DAS), 2 x weeding (21 DAS and 42 DAS). The second factor is the ratio of the population as sub-plots, consisting of 100% corn + 0% peanuts, 80% corn + 20% peanuts, 60% corn + 40% peanuts, 40 % corn + 60% peanuts, 20% corn + 80% peanuts. The results showed that the growth and yield of maize in the intercropping system with peanuts gave the same response to the population ratio at all weeding frequencies. The planting density of 40% maize + 60% peanuts produced the highest response on the variables of stem diameter (24.675 mm), plant fresh weight (667.51 grams) and biomass weight (79.924 grams). While the highest response to weeding frequency was 2 times (21 DAS and 42 DAS) only on plant fresh weight (588.08 grams).