Effects of Spacing, Nitrogen and Hormone Treatment on Pineapple in Swaziland

Abstract

Plant populations, nitrogen levels and the use of alpha naphthalene acetic acid (ANA) to reinforce natural flower differentiation were compared in a field experiment at Malkerns in the Swaziland Middleveld. Yield was raised by increasing plant population above 17,000 plants per acre, but reached a maximum at 23,000 plants per acre. Increased yield from denser planting occurred at the expense of fruit size and fruit set, and of sucker and slip production. Hormone counteracted the depressing effect of denser planting on fruit set and denser planting reduced sunburn damage and raised fruit acidity. 400 lb N per acre per crop increased yield over 200 lb N by increasing fruit size in the mother crop, and by increasing fruit size and set in the ratoon. Added nitrogen markedly reduced fruit acidity. ANA improved fruit set and therefore yield, without detrimental effects on fruit shape or quality. There are grounds for small increases in population above 17,000 plants per acre, for the use of ANA to reinforce natural flower differentiation and for the cautious use of the higher level of nitrogen fertilization.

Pineapple

“…Linear regression equations calculated from the data of Dodson (1968) and Wee (1969) show that fruit weight decreases approximately linearly with increasing planting density and correlation coefficients were 0.95 or better for both sets of data. Linear regression equations calculated from the data of Dodson (1968) and Wee (1969) show that fruit weight decreases approximately linearly with increasing planting density and correlation coefficients were 0.95 or better for both sets of data.…”

“…Linear regression equations calculated from the data of Dodson (1968) and Wee (1969) show that fruit weight decreases approximately linearly with increasing planting density and correlation coefficients were 0.95 or better for both sets of data. As planting density was increased, slips and suckers per plant, percent of plants fruiting, fruit weights, and fruit sugars all decreased while fruit acid increased (Wee, 1969;Mitchell and Nicholson, 1965;Dodson, 1968;Su, 1969). In all instances cited, the decrease in fruit weight per increase of 1000 plants ha" 1 was both a function of variety and of environment (presumably including quality of management).…”

“…The annual rainfall in various areas ranges from a low of 565 mm on the Island of Molokai, Hawaii (Noffsinger, 1961b) to 3550 mm at Neufchateau, Tkatchenko, 1947 Malkerns, Swaziland 26°30'S 16.8 28 4 955 Dodson, 1968 Ö A11 potential (ρ) or actual (a) evaporation data and some of the rainfall data are from Thornthwaite, C. W. Associates Publications in Climatology, Centerton, New Jersey.…”

Título en español

“…Research has been done on plant density and fertilizer requirements with other pineapple varieties in the northern coastal plain of Puerto Rico (10,12,14,15). Furthermore, it is well known that spacing and manuring are among the most important agronomic practices in pineapple cultivation (1,4,9,11,16,17). However, very little research has been conducted on agronomic practices regarding the Cabezona cultivar.…”