Tillage and Nutrient Management Strategies to Improve the Performances of Little Millet under Irrigated Condition

Small millets are “miracle crops” because of its multifaceted use, commonly known as nutri-cereals due to its high contribution on health benefits. Nutri-cereals are mostly grown in the developing nations for both human consumption and animal nourishment. These small grain cereals are found to be domesticated and considered as the “crops of antiquity” because of its inherent tolerant capacity against drought, pest and disease resistance mechanism (Devi et al., 2014). India is the world top millet producer with a yearly output of around 12.46 million metric tonnes from an area of 8.87 million hectares. Because of high beneficiary rate, increased awareness over consumer and shifted their main preferences on millet consumption (Prashanthi and Reddy, 2023). Although millets have recently gained more attention for their various food and health benefits and also well adaptation to adverse environmental conditions. But their productivity has remained low and needs to be boosted to enhance their utilization as a food crop (Numan et al., 2021).
       
Little millet (Panicum sumatrense L.) is a short-lived crop, fast germination, nutrient rich and resilient to harsh drought and water logging conditions. The states of Karnataka, Madhya Pradesh andhra Pradesh, Tamil Nadu, Gujarat, Chhattisgarh and Maharashtra where primarily cultivated. It is one among the six small millets grown in most of the regions of scanty and erratic rainfall on poor and marginal soils. Owing to its high nutritional values, the demand for little millet is increasing today particularly from the people suffering from diabetics (Himasree et al., 2021). Indiscriminate use of synthetic fertilizers and faulty management practices viz., nutrient, moisture stress and nutritional quality had greater constraints and threatened the sustainability of millet productivity and soil health condition (Nainwal et al., 2018 and Mubeena et al., 2019).
       
Soil tillage is a necessary practice in crop production, has a significant impact on soil properties, crop yield and soil-plant systems through higher nutrient use efficiency. Tilling of soil also had greater impact of microbial activity which influences soil aeration, moisture and temperature (Tripathi et al., 2007).
       
Recently, organic manures usage in crop production was tremendously increasing because of it positive responses led to improve soil fertility, productivity and strengthen the ecological status. Organic farming aims to reduce the use of external inputs and maximization of crop productivity resulted well in enhancing the soil quality by higher soil enzymatic activities (Shukla et al., 2011). Increase in demand of non-systematic information on nutrient management in millet cultivation, it is necessary to develop and focus their attention towards the enhancement on millet productivity and quality which creates an enabling environment for millet farmers. In addition to soil fertility status and crop productivity, organic nutrient sources with appropriate tillage practices showed better management method in little millet production. Therefore, the present study was designed to investigate the effect of tillage and different organic nutrient management on the growth and yield of little millet.

Soil and site description
 
A field experiment was performed during the summer and rabi season, 2022 at the experimental farm of Department of Agronomy, Tamil Nadu Agricultural University, Coimbatore. The soil of the experimental site was sandy clay loam in texture, slightly alkaline in nature. The experimental site was located in the western zone of Tamil Nadu at longitude of 76°97'E and latitude of 11°08'N with an elevation of 426 m above MSL.
 
Experimental setup
 
The experimental layout was done using strip plot design with three replicates consists of two factors viz., main plot (vertical strips) and sub plot (horizontal strips).  The treatment details are:
 
Tillage practices (Vertical strips)
 
T₁- Conventional tillage (Disc plough + Cultivator + Rotovator).
T₂- Farmer’s practice (Cultivator + Rotovator).
 
Nutrient management practices (Horizontal strips)
 
N₁-  FYM @ 12.5 t ha^-1 + Foliar spray of 3% panchagavya on 30^th DAS + 3% vermiwash on 45^th DAS.
N₂-  EFYM @ 1 t ha^-1 + Foliar spray of 3% panchagavya on 30^th DAS +5% egg amino acid on 45^th DAS.
N₃- VC @ 2.5 t ha^-1 + Foliar spray of 3% panchagavya on 30^th DAS + 3% vermiwash on 45^th DAS.
N₄- EVC @ 1 t ha^-1 + Foliar spray of 3% panchagavya on 30^th DAS+ 5% egg amino acid on 45^th DAS.
N₅- GM @ 2.5 t ha^-1 + Foliar spray of 3% panchagavya on 30^th DAS+ 5% vermiwash on 45^th DAS.
N₆- RDF of NPK fertilizers + Foliar spray of water on 30^th and 45^th DAS.
N₇- Absolute control.
 
Crop husbandry and cultivation practices
 
In conventional tillage, the field was ploughed with disc plough to break the hard pan followed by cultivator and rotovator to get fine seed bed and whereas in farmers practice, the field preparation was done with cultivator followed by rotovator. First sowing was done in the month of February, 2022 whereas second sowing was done during September 2022, respectively. The size of each plot was 7 m x 5 m and it was separated by a buffer channel with the distance of 60 cm to reduce the impact of different treatments. Organic and inorganic nutrient sources were applied as per the treatment schedule. Little millet (ATL 1) seeds were sown by line sowing method with inter-row distance of 25 cm and intra row distance of 10cm respectively. Data on growth parameters and yield attributes of little millet were observed. Data on growth parameters viz., plant height, leaf area index, number of tillers, internode tillers, internode length and yield attributes viz., number of productive tillers, panicle length, panicle weight of little millet was observed.
 
Statistical analysis
 
Statistical analyses of data were carried out for strip plot design. Data were analysed using R Studio as per methods suggested by Gomez and Gomez (1984). Crop data were subjected to the analysis of variance and least significant difference at probability level ≤ 0.05. The non-significant differences were denoted as NS.

Effect of tillage and nutrient management practices on growth parameters
 
The growth parameters viz., plant height, number of tillers, leaf area index, number of tillers per plant, internode tillers and internode length of little millet were significantly influenced by tillage and nutrient management practices.
 
Plant height
 
Among tillage system and nutrient management practices, conventional tillage found to be more responsive than the farmer’s practice. From the Table 1 and 2, the conventional tillage with enriched vermicompost @ 1t ha^-1 with foliar spray of 3% panchagavya on 30^th DAS + 5% egg amino acid on 45^th DAS (T₁N₄) has recorded higher plant height during both the season compared to other treatments. This might be due to the higher availability of nutrients from enriched vermicompost by enhanced activity of soil microorganism could convert organic to inorganic available form of nutrients. In addition to that, higher availability of nitrogen from enriched vermicompost as well as foliar nutrition at critical stages supplies good amount of plant nutrients and essential amino acids from panchagavya and egg amino acid leads to increase the plant height at various stages. These was in accordance with somasundaram et al., (2020) and Priyanka et al., (2019).
 

 

 
Leaf area index
 
Higher leaf area index was observed in the conventional tillage with enriched vermicompost @ 1t ha^-1 with foliar spray of 3% panchagavya on 30^th DAS + 5% egg amino acid on 45^th DAS (T₁N₄) might be due to application on essential nutrients and growth promoting substances at critical stages increases leaf number, leaf size which leads to better uptake of nutrients. Maximum LAI at peak flowering stage mainly due to high photosynthetic activity simultaneously increases the chlorophyll production through enriched organic sources in the form of soil and foliar application (Thesiya et al., 2019 and Gowda et al., 2018). The lowest leaf area index was obtained in the control treatment plot (N₇) under both the tillage system over the seasons. The resultant data analysis was given in the Table 1 and 2.
 
Number of tillers
 
From the experiment, Conventional tillage (Disc plough + Cultivator + Rotovator) significantly influenced the number of tillers per plant at 30 DAS (7.48 and 7.27), 60 DAS (9.88 and 9.21) and at harvest (10.25 and 10.02) during summer and rabi season, respectively. It also found that, decreased number of tillers per plant was observed with the farmer’s practice (Cultivator + Rotovator) during both the season.  Among the nutrient management practices, the plot treated with enriched vermicompost @ 1 t ha^-1 with foliar spray of 3% panchagavya on 30^th DAS + 5% egg amino acid on 45^th DAS had greater influence on yield attributes during summer and rabi season viz., maximum number of tillers were obtained at 30 DAS (7.93), 60 DAS (10.52) and at harvest (10.80) in the summer season and in the rabi season, the number of tillers at 30 DAS (7.82), 60 DAS (9.74) and at harvest (10.55), respectively. Adoption of tillage practices and organic manures had positive effect on physical, chemical and biological properties of soil tend to improve the capacity of nutrient uptake due to the presence of soil microbes. Foliar application of panchagavya and egg amino acid as foliar spray increases the availability of macro, micronutrients and growth hormones in addition to the presence of huge beneficial microbial population stimulates the crop growth characteristics such as pant height and more number of tillers. These results are in accordance with the findings of Priyanka et al., (2019).
 
Internode tillers and Internode length
 
Similarly, number of internode tillers and internode length at 60 DAS and at harvest were also significantly increased by combined effect of tillage and nutrient management during both the season (Fig 1 and Fig 2). The maximum number of internode tillers and internode length were obtained with enriched vermicompost @ 1t ha^-1 with foliar spray of 3% panchagavya on 30^th DAS + 5% egg amino acid on 45^th DAS under both the tillage practices followed by the enriched farm yard manure @ 1 t ha^-1 + foliar spray of 3% panchagavya on 30^th DAS +5% egg amino acid on 45^th DAS. This might be due to higher availability of nutrients from the soil as well as foliar nutrition increases the cell growth, cell elongation and development. These results were found to be similar with the findings of Ronanki et al., (2018) and Seth et al., (2020).
 

 


Effect of tillage and nutrient management practices on root length
 
Effect of tillage and nutrient management practices had significant influences on the root growth and development. From the observation, conventional tillage significantly influenced the root length at 30 DAS (15.77 cm), 60 DAS (21.22 cm) and at harvest (22.29 cm) in the summer season whereas with rabi season, the root length at 30 DAS (15.41 cm), 60 DAS (20.09 cm) and at harvest (21.46 cm) respectively. Among the nutrient management practices, the maximum root length was obtained in the summer season at 30 DAS (15.36 cm), 60 DAS (21.04 cm) and at harvest (21.53 cm) whereas in the rabi season, the root length at 30 DAS (15.12 cm), 60 DAS (20.50 cm) and at harvest (20.97 cm) was found, respectively (Fig 3a and 3b). The reason for increased root length under conventional tillage system, mainly due to the changes in soil physical properties through tillage process enhanced the root growth that influence the root for greater uptake of water and nutrients. Besides, adequate availability of nutrients in soil solution improves root growth through water and nutrient uptake. Higher nutrient uptake leads to profuse more number of roots can markedly results in improve activities of growth and yield attributes in little millet. This is in conformity with earlier findings of Yadav et al., (2012) and Louhar et al., (2020). The mean minimum root length was found with farmer’s tillage practices and in the control treatment (N₇) at during both summer and rabi season, respectively.
 

 
Effect of tillage and nutrient management practices on the yield attributes
 
Yield attributes such as number of productive tillers per hill, panicle length and panicle weight were significantly influenced mainly due to adoption of nutrient management practices. Conventional tillage plot applied with enriched vermicompost @ 1 t ha^-1 followed by foliar spray of 3% panchagavya on 30^th DAS and 5% egg amino acid on 45^th DAS (T₁N₄) during both the season resulted more number of productive tillers, maximum panicle length and weight.
       
From the experiment, it was found that among the two tillage practices, conventional tillage practice (T₁) resulted with increased number of productive tillers hil^l1 (7.91), panicle length (26.85 cm) and panicle weight (2.04 g) whereas with farmer’s practices (T₂), number of productive tillers hill^-1 (7.27), panicle length (26.37 cm) and panicle weight (1.93 g) were obtained at harvest stages during summer season. Similarly, highest yield attributes were obtained higher with conventional tillage than farmer’s practices in the rabi season. It might be due to improved changes in physical condition of soil which tends to enhance the nutrient uptake and resulted well in better yield attributes.
       
Among the nutrient management practices, the plot treated with enriched vermicompost @ 1t ha^-1 with foliar spray of 3% panchagavya on 30^th DAS + 5% egg amino acid on 45^th DAS had greater influence on yield attributes during summer and rabi season viz., maximum number of productive tillers (8.15 and 7.63 hill^-1), panicle length (27.30 and 26.72 cm) and panicle weight (2.08 and 2.06g) were obtained, respectively. It was found on par with the treatment enriched farm yard manure @ 1 t ha^-1 along with foliar spray of 3% panchagavya on 30^th DAS + 5% egg amino acid on 45^th DAS. These might be due superiority of organics might have been induced by increased and prolonged availability of nutrients, resulting in better utilization of applied nutrients from soil through soil microorganism activities. Higher photosynthetic and enzymatic activity could be the reason for greater nutrient uptake by plants which involves in the enhancement of yield characteristics. Similarly plants absorb more nutrients from the soil and transform it into useful sink. These results were in consonance with earlier findings of Bana et al., (2012) and Krupashree et al., (2022). The lowest productive tillers were noted in control plot (N₇) under both tillage practices during both summer and rabi season. This might be due to non-application of nutrient supplements to plants at critical stages results in reduced tiller production which directly showed the negative impact on yield attributes of little millet. The results of data were given in the Table 1 and 2.

From the above study, it could be inferred that conventionally tilled little millet has greater impact on the crop productivity than the farmer’s practice. During both summer and rabi season, conventional tillage system (Disc plough + Cultivator + Rotovator) with application of enriched vermicompost @ 1 t ha^-1 followed by foliar spray of 3% panchagavya on 30^th DAS and 5% egg amino acid on 45^th DAS showed the better performances of little millet with respect to growth and yield characteristics under irrigated condition. Furthermore, use of enriched organic manures not only enriches crop growth, it also preserves the soil health to produce healthy and quality grain, which is the basis of human health, ultimately determined by the soil fertility.