MSc

The study entitled “Standardization of agrotechniques in spinach beet (Beta vulgaris L. var. bengalensis)” was carried out at College of Agriculture, Vellayani, to standardize the planting geometry, nutrient management practice and number of harvests for economic yield and quality in spinach beet under rain shelter condition and to assess the effect on soil chemical and biological properties. The experiment was laid out in randomized block design in three replications during October 2019 to January 2020 with the variety All Green. The treatments included two spacings (s1: 20 cm x 10 cm; s2: 30 cm x 10 cm), two nutrient management practices (n1: inorganic sources; n2: organic sources) and three number of harvests (h1: four harvests; h2: five harvests; h3: six harvests). The NPK dose adopted was 80:40: 80 kg ha-1, one fourth N and K, full P were given as basal, remaining N and K, in splits as top dressing, 20 days after sowing (DAS) and after each harvest. The organic sources used were vermicompost, rock phosphate, arbscular mycorhizhal fungi (AMF) and wood ash, and the inorganic sources, urea, rajphos and muriate of potash.
The results of the experiment revealed that among the spacings tried, plant height (30, 40, 60 and 70 DAS), leaf area index (LAI) and leaf yield per 10 m2 were higher in the closer spacing, while per plant leaf area, number of leaves harvested and yields were significantly the highest in the wider spacing, s2. Among the nutrient sources, plant height (30, 40 and 60 DAS), leaf area, LAI and leaf yield were significantly higher in inorganic nutrient management. Leaf area, LAI and leaf yields were significantly the highest for the treatment with six harvests (h3) followed by h2 and h1.
The interaction effects of S x N and S x H on leaf yields were significant. Among S x N interactions, s1n1 recorded significantly higher leaf yield per 10 m2 (14.07 kg) and among the S x H interactions, s2h3 recorded the highest leaf yield per plant (111.56 g ) whereas s1h3 showed the highest leaf yield per 10 m2 (16.10 kg). The treatment combination s1n1h3 recorded the highest LAI (1.93) and leaf yield per 10 m2 (17.76 kg).
Nutrient uptake (N, P and K) were the highest in s2, n1 and h3. Quality parameters (vitamins A and C, protein and chlorophyll content) were comparatively higher in the leaves of third harvest. Vitamin A and C content were highest in n2 while protein and chlorophyll content were higher in n1. S x N x H interaction was significant for the protein content alone.
The soil properties did not show significant variations with spacing except available P status, which was higher in s2. Organic C, available N and K status were significantly higher in n2 and declined with the increase in number of harvests, higher contents were recorded in h1. The combination of s1n2h1 registered the highest available K status in soil. Soil microbial counts were significantly higher for n2 and the variations in fungal counts were significant for S x N, S x H and N x H interactions.
Economic analysis revealed that gross and net income from 10 m2 and benefit cost ratios were the highest for the combination of closer spacing, inorganic nutrient management and six harvest, s1n1h3, the values being (
888,
406 and 1.84 respectively).
Based on the results, the most suitable combination of agro techniques for economic yield in spinach beet under rain shelter condition include, closer spacing of 20 cm x 10 cm (s1), NPK dose of 80: 40: 80 kg ha-1 through inorganic sources (n1) and six harvests (h3). Considering the quality (vitamin A and C), organic nutrition (n2) proved to be superior and contents were the highest in the leaves of third harvest. The treatment combinations favourably influenced the soil nutrient status and microbial counts, higher values were recorded for organic nutrient management.