A STUDY OF KING GRASS (PENNISETUM-PURPUREUM SP) MUTANTS OBTAINED BY NUCLEAR TECHNIQUES AND CHEMICAL MUTAGENS .5. PIGMENTS

The green pigments and their absorption of king grass (Pennisetum purp ureum) mutants obtained by the application of nuclear techniques (CUBA MF 1000, 12, 18, 24, 30, 40 and 50) and chemical mutagens (CUBA MQ 1 and 2) were studied in a random block design with 4 replications. Ther e were no differences between mutants for the chlorophyll a contents i n the dry period but the rainy period the CUBA MF 12, 18,30 and 50 (3. 77, 3.56, 3.44 and 3.66 mg/dm(2), respectively) surpassed (P < 0.01) t he king grass (2.72 mg/dm(2)). Then were no differences between mutant s for the chlorophyll b contents in the dry period and in the rainy pe riod, with the exception of the CUBA MF 24, 40, CUBA MQ 1 and 2, the r est surpassed (P < 0.01) the king grass (1.08 mg/dm(2). The carotenoid contents showed differences between mutants and values ranged between 1.69 and 2.13 mg/dm(2) in the dry period, and from 0.43 to 0.68 in th e rainy period. All plants showed the highest light absorption at 420 and 660 nm varying with the amplitude and intensity. The variation and the importance of the indicators studied as well as their usefulness to determine variability between mutants is discussed.