Effect of vermiwash foliar sprays on yield contributing characteristics and quality of okra grown in inceptisol

Introduction

Okra (Abelmoschus esculentus) is one of the significant vegetable crops in India. It is popularly known as Lady's finger or "Bhindi". Okra is generally selfpollinated belongs to the Malvaceae family native to Africa. It is grown all across the tropical and subtropical regions as well as in the warmer climates of temperate regions (Basavaraja et al., 2009) [2] . Okra scientifically known as Abelmoschus esculentus is a vegetable crop that is economically important and grown in tropical and sub-tropical region across the world. The crop originates from West Africa and can be grown as either annual or perennial. Reaching a height of 0.5 to 4 meters. It is a heat and drought-tolerant crop, suitable both as a garden crop and on large commercial farms. Okra is grown commercially in India, Turkey, Iran, regions of Africa, the Southern United States and Japan countries. In England, it is known as Lady's Finger, in the U.S., it's called Gumbo and in India, it is referred to as Bhendi. Okra is rich in antioxidants and serves as primary source of Ca, K, vitamins and other minerals. India is the world's largest producer of okra among vegetables (FAO 2021) [6] . The country's diverse climate supports the availability of a wide range of fresh produce throughout the year. Okra is high in minerals including Ca, K, Cu, Fe, P, Mg, Zn and Manganese these seeds are also high in alpha-tocopherol (Petropoulos et al., 2018; Elkhalifa et al., 2020) [9,4] . Okra fruit has a high moisture content and is also rich in nutrients. It is an important source of vitamins, minerals, and carbohydrates, which are present in the form of mucilage (Tiwari et al., 2014) [12] .

Materials and Methods

This chapter comprises the details about the materials used and the methods adopted during the course of present investigation entitled as "Effect of Vermiwash Foliar Sprays on Growth and Yield contributing characteristics of Okra in Inceptisol". The experiment was carried out during Kharif season 2023-24.

Materials 2. 1. 1 Experimental site and Location

The experiment was laid out during kharif 2023-24 at Research Farm of Division of Soil Science, Dr. Sharadchandra Pawar College of Agriculture, Baramati Maharashtra (India). The location of the experimental farm lies between 18.14 0 latitude and 74.54 0 longitude.

Climate and weather conditions

The climate was classified as semi-arid tropical, with an average annual precipitation of 408.3 mm. The rainfall was torrential, irregular, scanty and uneven distribution. The meteorological observation recorded during 2023-24. The numbers of rainy days were 26 days. The mean annual maximum and minimum temperatures were ranged from 28.48 °C to 37.45 °C and 15.27 °C to 22.17 °C respectively.

Soil

The soil of the experimental field was medium deep black, belonging to Inceptisol order. The soil samples were collected randomly with the help of auger at a depth of 0-20 cm before starting the experimental research work. The chemical analysis was done in the Division of Soil Science, Dr. Sharadchandra Pawar College of Agriculture, Baramati. A composite soil sample was prepared and analysed for its various soil properties. The soil pH was moderately alkaline (8.4), electrical conductivity is normal (0.44 dSm -1 ), medium organic carbon (0.47%) and medium calcareous in nature (5.84%). The soil was low in available N, moderate in available P and moderately high in available K content. The micronutrient status in soil was sufficient in all micronutrients.

Design of Experiment

The field experiment was conducted in Randomized Block Design (RBD) with 3 replications and 8 treatments in each replication.

Treatment Details

The experimental details of treatments, which were comprised 8 treatments are presented in Table 2.1 100% GRDF 150:100:100 (N: P2O5: K2O Kg ha -1 ) T3 75% GRDF + 10% Vermiwash spray T4 75% GRDF + 20% Vermiwash spray T5 75% GRDF + 30% Vermiwash spray T6 100% GRDF + 10% Vermiwash spray T7 100% GRDF + 20% Vermiwash spray T8 100% GRDF + 30% Vermiwash spray Note: FYM-a common dose of FYM was applied @ 20 t ha -1 to all the treatments. GRDF-150:100:100 (N: P2O5: K2O) kg ha -1 was be applied to all the treatments.

Fertilizer application

RDF of 150:100:100 (N: P₂O₅: K₂O) kg ha⁻¹ was applied with phosphorus given as a basal dose and nitrogen and potassium administered in three split doses. Additionally, three vermiwash sprays were applied treatment-wise at 30, 60 and 90 DAS.

Height of plant was recorded from the base just above the soil surface to growing point of the plant after 25, 45 and 65 days after sowing.

Leaf Area (dm 2)

Leaf area was recorded with the help of leaf area meter of 3 rd top most leaf (i.e. photo synthetically active) in selected plants was recorded after 25, 45 and 65 days after sowing.

The fruit length was measured from selected five plants of each treatment with the help of scale and then average was recorded.

Number of fruit plant -1

The number of fruits harvested from five selected plants in each treatment was collected during each picking, counted and average fruits per plant was calculated.

The weight of five fruits was recorded separately with the help of digital weighing balance and average was worked out for each treatment.

Chlorophyll content

Chlorophyll content was determined from the plant's leaves by using an automatic SPAD meter. The SPAD values were recorded 5 days after vermiwash spray by clamping the SPAD sensor over the fully expanded five leaves from each tagged plant Shibaeva et al. (2020) [11] .

Fruit yield per plant

The weight of fruits per plant harvested from randomly tagged five plants from each treatment and each replication was noted down at each picking. The total weight of fruits harvested in each picking was computed, averaged and expressed in weight per plant in grams.

Fruit yield per plot

The weight of fruits harvested from each picking was recorded from each plot (including the tagged plants) and total yield per plot estimated by adding the yield of all the harvest expressed in kilograms per plot.

Fruit yield

Every week marketable fruits were picked from each plot and total yield was noted and calculated on ha -1 basis by using formulae given below.

Statistical Analysis

The data generated after the chemical and physical observations recorded from soil and plant as per the scheduled plan mentioned above was statistically analysed by adopting Randomized Block Design (RBD) as suggested by Panse and Sukhatme (1985) [8] .

Result and discussion

Effect of vermiwash foliar sprays on growth parameters of okra plant 3.1. Growth parameters 3.1.1 Plant height

Plant height was measured at 25, 45 and 65 DAS. At 25 DAS, there was non-significant variation in height. However, at 45 and 65 DAS, treatments with vermiwash, especially 100% GRDF + 30% vermiwash spray, significantly increased plant height compared to other treatments, with the highest heights recorded at 34.69 cm and 72.66 cm, respectively, while the control (water spray) showed the lowest growth at both stages. Similar result aligns with Ansari and Kumar (2010) [1] also reported that foliar spray of vermiwash and vermicompost increased the plant height.

Leaf area (dm 2 )

Leaf area in okra was measured at 25, 45 and 65 DAS. At 25 DAS, no significant differences were observed among the treatments. By 45 and 65 DAS, treatments with vermiwash, particularly 100% GRDF + 30% vermiwash spray, significantly increased leaf area, with the highest recorded values being 110.57 dm² at 45 DAS and 146.03 dm² at 65 DAS. The control treatment (GRDF +water spray) consistently showed the lowest leaf area at both stages. Similar result reported by Sanjutha et al. (2008) [10] and Yassen et al. (2020) [13] .

Chlorophyll content (SPAD units)

Vermiwash foliar sprays significantly increased chlorophyll content in okra. T 8 (100% GRDF + 30% vermiwash spray) consistently recorded the highest chlorophyll content at all stages (52.55, 59.19 and 59.85), followed by T 7 and T 6 . T 1 (GRDF + water spray) had the lowest chlorophyll content across all stages. Similar finding reported by Meghvansi et al. (2012) [7] found that the foliar spray of vermiwash increases chlorophyll content (SPAD value).

The result indicated that the effect of vermiwash foliar sprays on fruit length was between 10.82 cm and 13.04 cm with an overall average of 12.05 cm. Treatment T 8 recorded longest fruit length (13.04 cm) which was superior over all other treatments followed by T 7 (12.43 cm) and T6 (12.37 cm) which was at par with T 5 (12.32 cm) However, T 4 (12.01 cm) followed by T 3 (11.79 cm) was at par with T 2 (11.63 cm). T 1 (10.82 cm) measured the shortest fruit length among all treatments.

Number of fruits per plant

The T 8 (100% GRDF + 30% Vermiwash Spray) recorded the highest number of fruits plant -1 (32.53), which was significant over all other treatments and was followed by T 7 (32.27) and T 6 (31.20) which were at par with T 5 (30.67). However, T 4 (29.27) followed by T 3 (29.13 cm) was at par with T 2 (27.80). T 1 (GRDF + water spray) (24.77) recorded the lowest number of fruits plant -1 .

The highest fruit weight (24.32 gm) was recorded in the treatment with 100% GRDF + 30% vermiwash spray, followed by T 7 (24 gm) and T 6 (23.69 gm), which was on par with T 5 (21.85 gm). While the control treatment, T 1 (GRDF + water spray) recorded the lowest fruit weight at 16.54 gm. Similar results were observed by Dwivedi et al. (2018) [3] found that the highest fruit length (17.96 cm) and fruit weight (18.16 g) were achieved by applying the recommended NPK and five vermiwash sprays at weekly intervals of 30 DAS.

Conclusion

The application of vermiwash foliar sprays significantly influenced the growth and yield parameters of okra, including plant height, leaf area, number of fruits per plant, fruit length and fruit weight. Among the treatments, T 8 (100% GRDF + 30% Vermiwash Spray) showed the highest results, followed by T 7 , T 6 and T 5 , while T 1 (GRDF + Water Spray) exhibited the lowest growth and yield. Additionally, Chlorophyll content increased with the combined use of GRDF and vermiwash, with T 8 consistently having the highest chlorophyll levels across different growth stages (35, 45 and 55 DAS) whereas T 1 had the lowest. The overall effect of vermiwash foliar sprays on the growth and yieldcontributing characteristics of okra demonstrated a significantly influenced. It is possible to reduce 25% GRDF for the okra crop due to the use of vermiwash foliar sprays to maximize benefits and achieve higher yields as well as saving 25% GRDF.

References

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