Use of non-linear regression function to describe the profile of changes in yield and quality over the regrowth age to determine the appropriate harvesting time for Mombasa grass (Panicum maximum cv. Mombasa) in Nghia Dan, Nghe An
The study was conducted to determine the appropriate harvesting time of Mombasa grass in 3 different seasons in Nghia Dan, Nghe An. Secondary data were collected from 2016 to early 2021. Three growth functions,viz. Gompertz, Logistic, and Johnnson-Schumacher were used to describe the change in dry matter yield (DMY) and nutrient composition of Mombasa grass over 12 regrowth agesin 3 seasons, viz. rainy, dry, and hot. The most suitable function was determined based on the accuracy and reliability of the calculated functions. The optimal cutting interval for each season was determined based on the results of analysis of variance and regression analysis of DMY and nutrient composition of grass over regrowth age. The results showed that, Logistic function was the most suitable to describe profile of accumulated DMY over regrowth age The optimal Mombasa cutting interval in the Dry, Hot and Rainy seasons was 45, 35 and 30 days, respectively.
