Quantify the Storage Span of Bio Primed Seed using Biocontrol Agents and Liquid Biofertilizers in Moong Bean (Vigna radiata L.)

Green gram, popularly known as, is a major pulse crop in India. It may be planted as both a kharif and summer crop. India contributes more than 70% of worlds green gram production. In India during 2024-25, about 33.24 lakh ha area was covered under green gram as against 30.39 lakh ha during the same period in 2023-24. The important green gram producing state in the country is Rajasthan followed by Karnataka, Maharashtra, Madhya Pradesh Bihar and Andhra Pradesh. Mung bean plays an important role as a food security crop because of its nutritional quality as well as ability to survive in harsh environmental conditions such as arid and semiarid lands. They are mainly grown for human food, in the form of boiled dry beans, stew and flour while sprouts and immature pods as a vegetable (Yvonne et al., 2016). Agriculturally, mung beans are particularly valuable as a soil-enriching crop and are useful as cover crops and as green manure. Pulses can remain edible for several years if stored correctly. However, they are harder to store than cereals and are more susceptible to damage from insects and microorganisms. This leads to not only quantitative losses but also a decline in nutritional value due to vitamin loss and protein quality deterioration. There are two primary storage methods: bag and bulk. Bags can be stored outdoors or in warehouses, while bulk grain is kept in bins or silos of various sizes. Primed seeds are known to emerge faster, grow more vigorously and result in higher yields, which is especially important in unfavourable environmental conditions such as drought (Mamun et al., 2018). The main benefit of priming is the increase in the rate of germination at any temperature and the uniform emergence of seedlings from primed seeds at a faster rate than non-primed seeds due to limited adverse environmental exposure. This is due to the shortening of the lag phase or metabolic phase of the germination process. Biopriming could serve as a viable approach to enhance crop productivity as it improves the performance of plants under sub-optimal conditions (Roy et al., 2022). Storage is an essential component of seed programmes, which primarily aims at maintaining the high-quality standards of the seed from harvest till the time of sowing the crop in the next or successive seasons (Dadlani et al., 2023).

The experiment material consists of two variety NDM-1  and Sikha of mung bean in a complete randomised design with 04 replication for consecuting 02 Seasons i.e., 2023 and 2024 at Seed testing laboratory, Acharya Narendra Deva University of Agriculture and Technology, Kumarganj Ayodhya U.P. Concept of seed biopriming of (Taylor and Harmon, 1990) was adopted and seed biopriming was done in green gram are as follow.
       
According to different concentration (25%, 50% and 75%) of biocontrol agents and liquid biofertilizers (biofertilizers and biocontrol agents were collected from seed testing laboratory ANDUAT, Kumarganj Ayodhya U.P. Biofertilizers are in liquid form and biocontrol agents in liquid form) was suspended in one litre sterilized distilled water.
       
The seeds weighing 1 kg were immersed in the aforementioned solution and allowed to soak for six hours.      
The seeds, once soaked, were removed and laid out on blotter paper to dry.      
The seeds were immediately planted to evaluate their effectiveness in the field.     
Seeds that were hydrated and left untreated acted as the control group.        

Treatment includes Pseudomonas fluorescens, Trichoderma viridae, liquid Phosphobacteria and liquid Azospirillum, seeds with hydration priming and absolute control. The seed after biopriming and drying back to original moisture were packed in cloth bag and kept under ambient storage for a period of 9 months for two years. The 100 bio primed seeds were grown with the help of between paper method. The between paper method is a seed germination technique that involves placing seeds between two moist paper towels and rolling them into a towel. The rolled towels are then placed in a germination cabinet or room.
 
Observation taken
 
The populations of biological agents were tested at monthly intervals. The physical, physiological and seed health tests were carried out with the seed samples drawn at trimonthly interval. After 7 days of germination 10 seedling of each replication and treatment were randomly selected for recording the seed quality parameters except seed moisture content. The observation was recorded on eight qualitative characters, viz., seed moisture content (%), seed germination (%), seedling length (cm), seedling dry weight (gm) vigour index I, vigour index II and seed borne diseases. The data were analysed using analysis of variance, following the method by Panse and Sukhatme (1967).

The data can be recorded and analysed for seed quality parameters of mung bean. Different parameters are as follows.
 
Seed moisture content (%)
 
The seed moisture content (Mc) is the amount of water in the seed. It is usually expressed as a percentage or weight basis in seed-testing laboratory. The seed moisture content is the most vital parameter which influence the seed quality and storage life of the seed. The seed moisture content recorded with the help of digital moisture meter. Seed moisture content showed a significant difference due to seed biopriming treatment and period of storage. minimum moisture content observed during 3 months of storage as compared to 9 months (Fig 1).


 
Seed germination (%)
 
Germination was significantly influenced by seed biopriming storage period and their interactions. Irrespective of cloth bag and period of storage, during both two season (2023 and 2024) seed bio primed with TV @ 50% for 6 hrs i.e., T₆ could maintain the germination percentage 88.50% and 87.00% in both the varieties V₁ and V₂ respectively, when compared with other treatment. The reduction in germination over the period of storage was maximum. Germination percentage recorded at 3 months of storage is 91.09% and 90.06% in both the varieties V₁ and V₂ respectively was found to decrease to 86.13% and 84.94% in both the varieties V₁  and V₂ respectively at 9 months of storage. Non primed seeds recorded lower germination 82.50% in V₁ while 81.25% in V₂ at 9 months of storage (Table 1). The biosynthesis of pumpkin seeds with a combination of Azospirillum, Phosphobacteria and Pseudomonas fluorescens treatment improves the growth, yield and quality of plants (Sivakalai and Krishnaveni, 2017).


 
Seedling length (cm)
 
Seedling length was significantly influenced by seed biopriming storage period and their interactions. Irrespective of cloth bag and period of storage, during both two season (2023 and 2024) seed bio primed with TV @ 50% for 6 hrs i.e., T₆ could maintain the seedling length 28.50 cm and 26.17 cm in both the varieties V₁ and V₂ respectively, when compared with other treatment. The reduction in seedling length over the period of storage was maximum. Seedling length recorded at 3 months of storage is 36.49 cm and 33.05 cm in both the varieties V₁ and V₂ respectively was found to decrease to 25.44 cm and 23.22 cm in both the varieties V₁ and V₂ respectively at 9 months of storage. Non primed seeds recorded lower seedling length 22.62 cm in V₁ while 19.86 cm in V₂ at 9 month of storage (Table 2). Similarly, Vishwas et al. (2017) evaluated that seed priming with Rhizobium + Pseudomonas @ 10% for 12 hours recorded significantly higher germination percent (87%), speed of germination (77.11), shoot length (20.33 cm), root length (16.14 cm), seedling length (34.92 cm), seedling fresh weight (1200.3 mg), dry weight (150.4 mg), seedling vigour index I (2225.37),which is followed by seed priming with Rhizobium @ 10% for 12 hour (T₃) and lowest was recorded in T₀ (control).


 
Seedling dry weight (gm)
 
Seedling dry weight was significantly influenced by seed biopriming storage period and their interactions. Irrespective of cloth bag and period of storage, during both two season (2023 and 2024) seed bio primed with TV @ 50% for 6 hrs i.e., T₆ could maintain the seedling dry weight 0.160 g and 0.155 g in both the varieties V₁ and V₂ respectively, when compared with other treatment. The reduction in seedling dry weight over the period of storage was maximum. Non primed seeds recorded lower seedling dry weight 0.123 gm in V₁ while 0.110 gm in V₂ at 9 months of storage (Table 3). Similarly, Sajjan et al. (2021) evaluated in-vitro investigation of biopriming on seed quality parameters in green gram Vigna radiata (L.). Results showed that the seed bio primed with Rhizobium leguminosarum @ 20 per cent recorded higher seed germination percentage (90.50%), shoot length (19.27 cm), root length (12.38 cm), seedling length (31.65 cm), seedling dry weight (373.0 mg).


 
Seedling vigor index I
 
Seedling vigour index I was significantly influenced by seed biopriming storage period and their interactions. Irrespective of cloth bag and period of storage, during both two season (2023 and 2024) seed bio primed with TV @ 50% for 6 hrs i.e., T₆ could maintain the Vigor index I 2520.1 and 2276.0 in both the varieties V₁ and V₂ respectively, when compared with other treatment. The reduction in vigour index I over the period of storage was maximum. Vigor index I recorded at 3 months of storage is 3312.7 and 2978.9 in both the varieties V₁ and V₂ respectively was found to decrease to 2175.8 and 1973.3 in both the varieties V₁ and V₂ respectively at 9 months of storage. Non primed seeds recorded lower vigour I 1862.5 in V₁ while 1613.8 in V₂ at 9 months of storage (Table 4). Singh et al. (2015) studied with three mung bean cultivars SML 668, ML 818 and PAU 911 and showed the maximum vigour index I of 2578.8 in seed primed with Pseudomanas fluorescens.



Seedling vigor index II
 
Seedling vigour index II was significantly influenced by seed biopriming storage period and their interactions. Irrespective of cloth bag and period of storage, during both two season (2023 and 2024) seed bio primed with TV @ 50% for 6 hrs i.e., T₆ could maintain the Vigor index II 13.86 and 13.15 in both the varieties V₁ and V₂ respectively, when compared with other treatment. The reduction in vigour index II over the period of storage was maximum. Vigor index II recorded at 3 months of storage is 20.52 and 19.86 in both the varieties V₁ and V₂ respectively was found to decrease to 11.90 and 10.95 in both the varieties V₁ and V₂ respectively at 9 months of storage. Non primed seeds recorded lower vigour II 9.89 in V₁ while 8.72 in V₂ at 9 months of storage (Table 5). Jaisani et al. (2016) reported that in vitro application of T. viride, T. harzianum and T. virens conidial suspension to chickpea seeds gave significant results.


 
Seed borne diseases
 
Seed borne disease was significantly influenced by seed biopriming storage period and their interactions. Irrespective of cloth bag and period of storage, during both two season (2023 and 2024) seed bio primed with TV @ 50% for 6 hrs i.e., T₆ could maintain the seed borne disease 8.63 and 9.00 in both the varieties V₁ and V₂ respectively, when compared with other treatment. The increment in seed borne disease over the period of storage was maximum. Seed borne disease recorded at 3 months of storage is 4.80 and 5.46 in both the varieties V₁ and V₂ respectively was found to increase to 9.89 and 10.36 in both the varieties V₁ and V₂ respectively at 9 months of storage. Non primed seeds recorded highest seed borne disease 11.38% in V₁ while 12.38% in V₂ at 9 months of storage (Table 6). Similarly, Deshmukh et al., (2016) studied the effects of different seed treatments with soil amendments were used for controlling root rot incidence. Among them (T₆) FYM with seed treatment of T. harzianum 4 g/kg seed + PSB at 25 g/kg seed recorded the lowest root rot incidence (26.0%) followed by (T₃) R. phaseoli at 25 g/kg seed + P. fluorescens at 10 g/kg seed which recorded 32.0% root rot incidence whereas, maximum incidence of the disease was recorded in the control (83.3%).

Two-year lab experiment (during storage period) clearly suggests that usefulness of seed biopriming in moong bean by Pseudomonas fluorescens, Trichoderma viridae, Azospirilum and Phosphobacter for enhancing the germination and vigour in moong bean. This will improve plant health and give healthy produce. The best concentration and duration standardized for biopriming was Trichoderma viridae @ 50% for 6 hrs.

The authors thank the authorities of Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya, U.P. India for providing all the facilities to conduct this investigation.