Effect of foliar application of micronutrients on growth, fruit retention and yield parameters of acid lime (Citrus aurantifolia Swingle)

Abstract

The deficiency of micronutrients is widespread in Nepal, which results in poor growth, fruit drop and lower yield. June drop and pre-harvest drop reduce fruit retention and yield of Citrus. A study on the effects of micronutrients on June drop and pre-harvest drop of Citrus has not been conducted in Nepal and few in the global range. So, the effects of foliar application of micronutrients (Zn, B and Cu) were studied on plant growth, fruit retention and yield parameters of acid lime (Citrus aurantifolia Swingle) var. Sun Kagati-1. The findings revealed the significant effect of Zn alone or in combination with plant canopy spread under growth parameters. Zn and B alone or in combination significantly affected fruit retention and yield parameters of acid lime. Zn and/or B resulted in significant minimization of June drop and pre-harvest drop of fruits with a greater reduction in combination type treatments. Cu enhanced fruit weight and thereby led to greater yield. Treatment Zn (0.1%)+Cu (0.05%)+B (0.05%) was best on which fruit set was 26.14% higher as compared to control. Similarly, the June and pre-harvest drops were 18.52% and 5.18% lower in the treatment, respectively. Moreover, yield due to the treatment was 1.6 times greater than that of control as a result of higher fruit number and fruit weight. Thus, the application of Zn, B and Cu can be beneficial in obtaining a greater fruit set. Further, their role in the minimization of June and pre-harvest drop augments the fruit yield of acid lime.

Keywords:

• zinc
• boron
• copper
• Citrus
• fertilization
• fruit set
• June drop

PUBLIC INTEREST STATEMENT

Obtaining a greater and stable yield is pivotal for commercial Citrus cultivation, however poor plant growth and fruit drop can be challenging factors as this reduces yield. Various studies suggest that the problems can be ameliorated by the use of micronutrients since they are involved in various enzymatic processes that promote growth, increase fruit set and minimize fruit drop. Also, people of Nawalparasi East district are oblivion to micronutrient use and there is also a problem of fruit drop in Citrus orchards of the region. Thus, this study was conducted in acid lime to explore the effect of micronutrients on the minimization of fruit drop (June drop and pre-harvest drop) and impart cognizance of micronutrients’ use to obtain greater yield.

Acknowledgements

Mr Bishnu Prasad Sharma (Senior Agriculture Officer) and Mr Ravi Kiran Adhikari (Agriculture Officer) from Prime Minister Agriculture Modernization Project-Project Implementation Unit, Nawalparasi East are gratefully acknowledged for their immense help, inspiration, supervision and suggestion during the entire research period. We extend sincere commemoration to Mrs Yam Kumari Shrestha, Senior Horticulture Development Officer at National Centre for Fruit Development, Kirtipur, for time-to-time guidance and suggestions. We are also deeply indebted to numerous solicitous hands whose contribution has played a pivotal role.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors received no direct funding for this research.

Notes on contributors

Saurav Bastakoti

Mr Saurav Bastakoti is an agriculture graduate who passed bachelor’s degree in agriculture from Agriculture and Forestry University (AFU), Rampur, Chitwan, Nepal. He is the author of a booklet titled “Integrated Nutrient Management in Citrus fruits”. He executed the research as the main researcher and writer.

Mr Saurav Nepal and Ms Dipika Sharma also passed their bachelor’s degree in agriculture from AFU and assisted in writing this research.

Mr Arjun Kumar Shrestha, PhD is a Professor at the Department of Horticulture as well as Director at the Directorate of Research and Extension in AFU. He supervised this research and helped in research designing as well as writing. The essence of this research is its connection with the livelihood of Citrus farmers of Nawalparasi East district and its assistance to obtain greater income through improvement in yield.