Effect of harvest management on growth performance and seed yield of fodder oat (Avena sativa L.) in Rasuwa district, Nepal

Introduction

Supply of green and dry herbage for livestock production is a major problem during the winter season in Nepal. Oat (Avena sativa L.) is the major winter fodder and plays a vital role in filling the seasonal feed gap. Mostly, oat can be grown for green herbage, silage, and straw. As the need of animals for nutrients increases during the winter season, the demand for oat is increasing. Balancing herbage mass and seed production is a major concern for oat producing farmers by adopting effective management practices (Kim et al., 2006) [6] . However, the animal husbandry sector depends on consistent supply of fodder and seed throughout the nation. One of the most effective agronomic strategies for this implementation is harvest management. Oat is nutritious, versatile, has multicut ability with a high number of tillering capacity and can be grown to mitigate the fodder scarcity. Effective harvest management at an appropriate growth stage significantly affects growth, forage yield and seed quality (Tessema et al., 2010) [15] . Therefore, identification of the most suitable harvest days after sowing and then left for maximum seed production without any effect on seed quality is essential (Ahmad et al., 2014) [1] . However, the production of fodder seed has been limited in Nepal. The country needs a large amount of fodder seed. Due to scarcity, fodder seed are imported from foreign countries (Singh & Singh, 2019) [13] . Based on this background, the experiment was conducted to evaluate the effect of harvest management on growth performance, herbage production, as well as seed yield of fodder oats.

Materials and Methods

The experiment was carried out at 1850 masl, Dhunche, Rasuwa, Nepal during the F.Y. 2024/25. Oat seeds were sown on 07 th October, 2024 using a split plot design. Two varieties, Monida (A1) and Parbati (A2), were assigned to the main plots, while harvest managements were allocated to the sub-plots. The four different harvest managements were  B1: First cut at 30 days after sowing for fodder production, then left for seed production  B2: First cut at 45 days after sowing for fodder production, then left for seed production  B3: First cut at 60 days after sowing for fodder production, then left for seed production  B4: Zero cut for fodder production; only left for seed production Each treatment was replicated in three times. Seed was sown at the rate of 80kg/ha with 25 cm row to row spacing. Farmyard manure (FYM) was applied at the rate of 10 t/ha. Chemical fertilizers were applied at the rate of 80:60:40 kg/ha N:P:K. The full dose of FYM, phosphorus, and potassium, along with half of the nitrogen, was incorporated during final land preparation. The remaining nitrogen was applied in two split dose. The first half was top dressed one month after sowing, and the second half was top dressed one month after first harvest. For the zero-cut treatment, the second half of nitrogen was top dressed one month after the first application.

The growth parameters plant height, leaf length, leaf breadth and number of tillers per plant were recorded by selecting five plants randomly from each plot. The leaf area was calculate using formula = (leaf length x leaf breadth) x 0.75 (Musa & Usman, 2016) [7] . Green herbage was recorded from each 1x1 m 2 quadrat from each plot. 200 gram fresh sample was taken to estimate further dry herbage. Dry matter was determined by oven drying fresh herbage at a constant temperature of 72 o C

for 24-48 hours. At the time of seed maturity, fresh straw and seed production per square meter was measured. 1000 seed weight was also measured in gram. The production per square meter was converted to t/ha. All the datas were analyzed using R software (R Studio, 2020) [11] .

Results and Discussion

Plant performance and dry herbage yield at different harvest dates

Plant performance and dry herbage production at different harvest dates is presented on Table 1. There was no significant (p > 0.05) effect of the variety on plant height, leaf area, tiller number and dry herbage production. Furthermore, the harvest times had significant (p < 0.001) effect on plant height, leaf area, tiller number and dry herbage production. Plants harvested at 30 days after sowing had shorter plant height, smaller leaf area, fewer tillers, and less dry herbage compared to those harvested at 60 days. Additionally, the interaction between variety and harvest management was significantly (p < 0.001) affected plant height, leaf area, tiller number, and dry herbage production. Accordingly, the highest plant height, tiller numbers per plant, leaf area and dry herbage production, was obtained by both varieties if harvested at 60 days after sowing. This indicates that harvest timing is the dominant factor, while varietal differences remain minimal. The highest herbage production at the late stage of maturity was due to higher plant height, leaf length, leaf breadth, and tiller numbers (Amanullah et al., 2004) [2] . The difference herbage production at the same harvest period of different varieties may be due to different genetic trait. Varietal characteristics, climatic condition, and soil nature play a major role in herbage production (Baral et [3,8,14,16] .

Straw and seed production

Effect of harvest managements on plant growth, straw and seed yield of oat varieties is presented in Table 2. At the time of seed harvest time, the varieties of oat had similar effect (p > 0.05) on plant height, leaf area, straw yield, seed production and 1000 seed weight. However, harvest management significantly affected plant height (p < 0.001), leaf area (p < 0.001), fresh straw weight (p < 0.05), seed production (p < 0.05), and seed weight (p < 0.05). In addition, it was found that harvest management had similar effect (p > 0.05) on tiller numbers. Accordingly, the highest plant height leaf area, fresh straw weight, seed production and seed weight were obtained by zero harvest (no for fodder cut, harvested only at seed maturity stage), followed by first harvest at 30 days after sowing for fodder production and left for seed production. Seed quality was also superior, with the highest 1000-seed weight under this harvest date. The least plant height, leaf area, dry herbage, straw weight as well as seed yield and 1000 seed weight were found when fodder was harvested at 60 days after sowing. The interaction between variety and harvest management had significant effect (p < 0.05) on plant height, leaf area and fresh straw weight. However, the interaction between variety and harvest management had similar (p > 0.05) effect on seed yield, 1000 seed weight and tiller numbers. Accordingly, the highest plant height, leaf area, fresh straw weight was obtained by zero harvest (no for fodder cut, harvested only at seed maturity stage) on both varieties followed by first harvest at 30 days after sowing and then left for seed production. These findings are consistent with previous researchers. Harvest at any stage in multi cut varieties induces physiological stress redirecting energy towards plant regrowth rather reproductive development. The uncut fodder utilize full energy for both vegetative and reproductive growth leading higher herbage as well as more seed production. Accordingly, stress free condition enhance vegetative growth (Sadeghipour, 2009) [12] . Similarly, Croce et al. (2024) [5] reported that maximum photosynthesis increased the crop yield, which is consistent with our finding that maximum seed production was obtained under zero harvest treatment. Our results also highlighted the advantage of earlier harvest as compared to late. Furthermore, Rauf et al. (2021) [10] observed that earlier cut produced higher number of tillers and high yield as compared to late cut. As our finding Baral et al. (2024) [3] reported that varietal effect on seed yield is minimal. Additionally, Bhakuni et al. (2025) [4] reported that harvest times had significant effect on herbage production and fresh straw yield. This consistent to our finding that harvest time is more influential than variety.

Contributions of growth attributes on fresh straw and seed production

Contributions of plant height, leaf area and tiller numbers on fresh straw yield and seed production is presented in Table 3. However, Plant height (p < 0.05), leaf area (p < 0.05) and tiller numbers (p < 0.05) of fodder oat had significant contribution to fresh straw production. It revealed that fresh straw production was increased by 0.23 unit with one unit change in plant height, increased 0.14 unit with one unit change in leaf area and increased 0.07 unit with one unit change in tiller numbers. Plant height of fodder oat did not show significant effect on seed production (p > 0.05). However, leaf area and tiller number had significant effects (p < 0.05). It revealed that seed production was increased by 0.06 unit with one unit change in leaf area, as well as increased 0.09 unit with one unit change in tiller number. Our findings showed a positive correlation between the growth parameters of fodder oat (plant height, leaf area, and number of tillers) and fresh straw production. In addition to this, leaf area and tiller number were positively correlated with seed production. The higher number of tillers bears higher number of leaves per plant. This enhanced the photosynthetic efficiency that increased overall seed and fresh straw production. These findings were supported by previous studies by Pierce et al. (2014) [9] ; Amanullah, et al. (2004) [2] .

Conclusion

The study demonstrates that harvest management plays a significant role in balancing fodder and seed yield in oats, while varieties had little effect under the tested conditions. Harvest at late stage maximizes fodder yield, but delaying harvest hampered the seed and fresh straw production. Early harvest at 30 days after sowing provides good amount of herbage and seed. The highest amount of fresh straw and seed was produced under zero harvest (harvest only at seed maturity stage) and early harvest at 30 days after sowing for fodder and then left for seed production. Plant height, leaf area and number of tiller had significant correlation with fresh straw yield. However, leaf area and tiller number had significant correlation with seed production. These findings suggest that adopting harvest management can reduce the fodder scarcity and reliance on imported seed, thereby strengthen seed supply and support livestock production system.

Acknowledgement

AcknowledgmentsI would like to express my heartfelt gratitude to all staffs at Pasture and fodder Research Station, Dhunche, Rasuwa for their invaluable support in facilitating timely organizing experimental plots and data collection. Special thanks is extended to Mr Naba Raj Paudel for his dedicated assistance during data analysis process.

References

1. Ahmad M, Dar ZA, Habib M. A review on oat (Avena sativa L.) as a dual purpose crop. Scientific Research and Essays. 2014;9(4):52-59.
2. Amanullah PS, Zada K, Perveen S. Growth characters and productivity of oat varieties at Peshawar. Sarhad Journal of Agriculture. 2004;20(1):5-10.
3. Baral BR, Khanal B, Gorkhali NA. Evaluation of different fodder oats (Avena sativa L.) varieties for their herbage mass and seed production potentials in Rasuwa, Nepal. Jagriti -An Official Journal of Gandaki University. 2024;1(1):131-136.
4. Bhakuni K, Sabal SK, Bhattacharjee S, Kumar R, Ram H, Meena RK, et al. Optimizing varietal selection and cutting intervals for enhanced fodder productivity, quality and energy content in multi-cut oats. Indian Journal of Animal Sciences. 2025;95(9):789-798. doi:10.56093/ijans.v95i9.160317
5. Croce R, Silva EC, Cho YB, Ermakova M, Harbinson J, Lawson T, et al. Perspectives on improving photosynthesis to increase crop yield. The Plant Cell. 2024;36(10):3944-3973. doi:10.1093/plcell/koae132
6. Kim JD, Kim SG, Abuel SJ, Kwon CH, Shin CN, Ko KH, et al. Effect of location, season and variety on yield and quality of forage oat. Asian-Australasian Journal of Animal Sciences. 2006;19(7):970-977.
7. Musa UT, Usman TH. Leaf area determination for maize (Zea mays L.), okra (Abelmoschus esculentus L.) and cowpea (Vigna unguiculata L.) crops using linear measurements. Journal of Biology, Agriculture and Healthcare. 2016;6(4):103-111.
8. Pant SR, Ghimire RP, KC P, Upreti S. Growth and yield of different oat (Avena sativa) varieties in Lalitpur district of Nepal. Journal of Agriculture and Natural Resources. 2022;5(1):34-39. doi:10.3126/janr.v5i1.50394
9. Pierce S, Bottinelli A, Bassani I, Ceriani RM, Cerabolini BEL. How well do seed production traits correlate with leaf traits, whole-plant traits and plant ecological strategies? Plant Ecology. 2014;215(12):1351-1359.
10. Rauf A, Singh B, Dhaka AK. Performance of dualpurpose wheat as influenced by cutting and nitrogen schedules. Forage Research. 2021;47(1):79-83.
11. R Studio Team. R Studio: Integrated development for R. R Studio, PBC; 2020. http://www.rstudio.com
12. Singh SB, Singh N. Nepal livestock feed balance and strategies to address the feed deficit. Journal of Agriculture and Forestry University. 2019;3:159-171.
13. Singh VK, Singha AK, Takawle PS, Shindey DN, Shrivastav MK. Evaluation of different oat varieties for green fodder and seed production yield. International Journal of Recent Advances in Multidisciplinary Research. 2018;5(3):3668-3670.
14. Tessema ZK, Mihret J, Solomon M. Effect of defoliation frequency and cutting height on growth, dry matter yield and nutritive value of napier grass (Pennisetum purpureum (L.) Schumach). Grass and Forage Science. 2010;65(4):421-430.
15. Zaman QM, Hussain N, Aziz A, Hayat K. Performance of high-yielding oats varieties under agro-climatic conditions of DI Khan. Journal of Agriculture Research. 2006;44(1):29-36.