Fenologia e produtividade de progênies sexuada e assexuada de cajueiro comum e anão (Anacardium occidentale L.) sob irrigação

Abstract

The experiment was conducted at the Experimental Station of Pacajus Country (state of Ceará, Brazil) aiming to asses the vegetative and productive behavior of clones and progenies of cashew nut plants (Anacardium occidentale L.). Two dwarf clones (CCP 76 and CCP 09), two clones common type (C-CP-12 and C-CP-f7) 'and-two progenies (P-09 and P-07), from seeds of dwarf clone CCP-09 and of clone of common type C-CP-07, respectively, were tested under three irrigation levels: (I0: without irrigation; Ii: irrigation all year and I2: supplement irrigation during the rainy season). The experimental work was carried for three years. The experimental design was a randomized blocks with two factors: A - six levels (two dwarf clones; two common clones and two progenies) and B - three irrigation levels (I0, Ti and I2), with four replication in band arrangement. Variances and averages comparisons were done by orthogonal contrasts and for significance the F test was used. Results showed that plant vertical and lateral growth were in a continuos way for all germplasm with higher performances for the common clones and progenies. From the eleventh months of planting clones and progenies, in the three irrigation levels, exhibited bigger lateral growth that the vertical owe. Stem diameter was not a suitable parameter for estimation of plant height and canopy diameter until the twentieth month from the planting. The irrigation did not influence plant height, canopy diameter and flowering, although the stem diameter and fruiting had positively been influenced by the interaction irrigation level x germplasm. Fruiting occurred mainly in the second half of the year for clones and progenies under all irrigation levels. During the first two years of evaluation clones and progenies changed leaves all year round, irrespective of the irrigation leaves. For the first year of evaluation clones and progenies showed two peaks of leaf change: the first one in the middle of the rainy season and the second one at the end of the dry season. Irrespective of the irrigation level the dwarf clones and the progeny P-09 were the most precocious. Clones of common type behaved as intermediate while the progeny P-07 was the most late as far as the flowering, fruiting and young fruits fall were concerned. In the third year of evaluation the irrigation influenced clones and progenies by decreasing the number of young fruits fallen. The dwarf clone young fruit fall besides the best productivity. The dwarf clone CCP 09 is recommended for irrigated plantations.