Agronomy

EFFECT OF DIFFERENT PLANTING METHODS ON GROWTH AND YIELD PERFORMANCE OF RICE VARIETY BG 366

Wed, 01 Jan 2025 00:00:00 GMT

EFFECT OF DIFFERENT PLANTING METHODS ON GROWTH AND YIELD PERFORMANCE OF RICE VARIETY BG 366 Saththiyavahini, K; Pradheeban, L; Senthilkumaran, S Rice is the staple food for Sri Lankan people. Annual production of rice in Sri Lanka needs to be increased to feed the growing population and to maintain the self-sufficiency. Expanding the area under rice cultivation will not be possible in near future. Therefore, additional rice production has to come from increasing the productivity of grains. Choosing the best rice establishment method for higher yield and higher economic return is one of the ways to increase the productivity of land. A study was conducted at farmers’ field in 1.7 ha of land during Yala season 2024, to evaluate the effect of different planting methods (Dry seeding, Wet seeding, Seedlings broadcasting and Machine transplanting) on growth and yield performance of rice variety Bg 366. The experiment was laid out in RCBD with three replicates, and data were analyzed by using ANCOVA to enhance the accuracy of results due to large size experimental units. Data on plant growth and yield parameters were collected as plant height, flag leaf area, chlorophyll content of flag leaf, days taken to maturity, number of productive tillers m-2, weight of panicle, number of filled grains panicle-1, 1000 grain weight and grain yield. Cost of production and net income also were calculated for each planting method. Considering the growth parameters, higher plant height, higher chlorophyll content, higher flag leaf area were observed in both machine transplanting and seedlings broadcasting compared to direct seeding methods. Results showed that grain yield and net income were significantly higher in seedlings broadcasting method (6.84 t ha-1, Rs.241 700 ha-1 respectively) followed by Machine transplanting (5.81 t ha-1, Rs.194 400 ha-1respectively).This may be due to the quick establishment of seedlings with soil ball and production of the highest number of effective tillers in seedlings broadcasting method. Findings suggest that both seedlings broadcasting and machine transplanting were found to be most productive and economically viable methods of rice establishment than direct seeding.

Effect of different nutrient solutions on the growth and yield of water spinach (Ipomoea aquatica) and mint (Mentha spicata) under the non-circulating hydroponic system

Wed, 01 Jan 2025 00:00:00 GMT

Effect of different nutrient solutions on the growth and yield of water spinach (Ipomoea aquatica) and mint (Mentha spicata) under the non-circulating hydroponic system Yathurshini, M; Pragheeban, L Leafy vegetables are an essential component of a balanced diet due to their rich nutritional profile. However, producing high-quality leafy vegetables without the use of harmful agrochemicals remains a significant challenge in sustainable agriculture. In hydroponic systems, nutrient solutions like Albert’s solution offer controlled growth, but are costly and rely on nonorganic inputs, limiting their compatibility with organic cultivation. This study evaluated the effectiveness of different organic nutrient solutions on the growth and yield of leafy vegetables (water spinach and mint) in a non-circulating hydroponic system. The experiment was conducted in a Completely Randomized Design with six treatments: Albert’s solution (T1, control), Fish tonic (T2), Seaweed nutrient solution (T3), Jeewamruta (T4), Vermiwash (T5), and Vegetable waste nutrient solution (T6), each with four replicates. Growth parameters (plant height, number of leaves and branches, root length), quality parameter (chlorophyll content), and yield parameter (fresh weight of shoot) were recorded and analyzed using ANOVA in SAS 9.1. Among the treatments, both Albert’s solution and Jeewamruta showed statistically similar and superior performance in water spinach for key growth parameters, except root length and overall biomass accumulation. Vermiwash resulted in the longest root length. In case of mint, Albert’s solution and Vegetable waste nutrient solution showed similarly high values for key growth parameters except root length and overall biomass accumulation, with no significant differences between them. Again, Vermiwash recorded the longest root length in mint. In water spinach, Jeewamruta showed comparable effectiveness to Albert’s solution. Similarly, the Vegetable waste nutrient solution proved equally effective as Albert’s solution in enhancing growth performance in mint. These findings indicate that Jeewamruta and Vegetable waste nutrient solution can be suggested as cost-effective, sustainable, and environmentally friendly alternatives to synthetic hydroponic nutrient solutions, particularly for the cultivation of water spinach and mint.

Effect of Rhizobium inoculation and inorganic fertilizer levels on growth, yield and shelling percentage of two groundnut varieties

Wed, 01 Jan 2025 00:00:00 GMT

Effect of Rhizobium inoculation and inorganic fertilizer levels on growth, yield and shelling percentage of two groundnut varieties Malinda, P.G.Isuru; Pradheean, L Optimizing groundnut yield through effective use of biological and inorganic inputs is essential for sustainable production. This study evaluated the effect of Rhizobium inoculation and different levels of inorganic fertilizer on the growth, yield, and shelling percentage of groundnuts in the Killinochchi District from May to September 2024. A two-factor factorial experiment was conducted in a randomized complete block design with three blocks. Within each block, 12 treatment combinations were applied. The first factor included six fertilizer treatments with or without Rhizobium inoculation: (F1 (0% Rhizobium + 100% Fertilizer), F2 (Rhizobium + 0% Fertilizer), F3 (Rhizobium + 100% Fertilizer), F4 (Rhizobium + 75% Fertilizer), F5 (Rhizobium + 50% Fertilizer), F6 (Rhizobium + 25% Fertilizer). The second factor was the groundnut variety (V1: ANKG2 (Lanka Jambo) and V2: Tissa,). All agronomic practices followed the Department of Agriculture, Sri Lanka guidelines, except for the fertilizer levels. Data on growth parameters, number of active and inactive nodules, yield components, and shelling percentage were collected and analyzed using ANOVA in SAS 9.1, with mean separation by Duncan’s Multiple Range Test. The interaction effect between the two factors was non-significant. However, both factors significantly (p < 0.05) affected plant growth, yield and shelling percentage. Total nodule number and active nodules were significantly higher in ANKG2. This variety also showed superior yield metrics, including 100-seed weight and shelling percentage. while Tissa variety recorded the highest pod count. Significantly the highest dry weight at harvest, yield and shelling percentage were observed in F3 (Rhizobium + 100% Fertilizer), while F2 (Rhizobium + 0% Fertilizer), recorded the lowest. No significant difference was found between F4 (75% fertilizer + inoculation) and F1 (conventional practice). It can be concluded that the combination of ANKG2 with rhizobium inoculation and 100 % recommended fertilizer is the most effective for maximizing yield in Kilinochchi District followed by F4 (75% fertilizer + Rhizobium inoculation) as a more input-efficient alternative

Estimating structural parameters of a complex mixed conifer-broadleaf forest using UAV photogrammetry

Mon, 01 Jan 2024 00:00:00 GMT

Estimating structural parameters of a complex mixed conifer-broadleaf forest using UAV photogrammetry Jeyavanan, K.; Owari, T.; Tsuyuki, S.; Hiroshima, T. Estimating forest structural parameters in structurally complex forests remains as challengi ng. Use of highresolution imagery, suitable remote sensing variables and models will highly contribute to improve estimation accuracy. We used high- resolution UAV RGB imagery to estimate forest structural parameters in a mixed conifer broadleaf forest at the University of Tokyo Hokkaido Forest. In addition to DBH, spatial posit ion and height of dominant trees were measured in the inventory plots. Pix4D software was used to derive dense point clouds, digital surface model, canopy height model (CHM) and o rthomosaics. Mean, maximum, percentile and standard deviation of CHM were validated w ith the height and DBH, basal area (BA), stem volume (V) and tree carbon stock (CST). 75- 99 % percentile heights of CHM were highly correlated with dominant tree height, while CH M mean was highly correlated with BA, V, and CST. Conifer dominated plots had a higher es timation accuracy with dominant tree height.