Background:

Cenchrus purpureus vc. Cuba OM-22 is a promising forage type for Venezuelan cattle raising, due to its high production and quality. Aim. To evaluate the agronomic indicators, and their relation to the plant age, and climatic elements, during the rainy and dry seasons.

Methods:

A uniformity cut was established at the end of each period. Height, length, and width of the fourth pair of fully-open leaves and internodes, leaf content and stems, foliar area, and yields, were determined every 15 days, for 75 days, following a randomized block design with four replications. The values of variance analysis were compared, according to the test of multiple range comparison of means, and the regression equations were set up.

Results:

The agronomic variables showed significant differences (p<0.05) with re-shoot age increase, having a marked effect on the percentage of leaves and stems. Multiple linear equations (P<0.001) (R2>0.90) on yield and percentage of age-related leaves and stems, as well as for the mean and maximum temperatures, and precipitations, were set. The performance curve kept the logarithmic phase up to 75 days, then higher values were observed.

Conclusions:

Age and the climatic elements showed a marked effect on the agronomic indicators. The regression models showed a high correlation between the variables studied with the maximum temperature, and precipitations.