Influence of Liming and Soil pH on Sorghum (S. Bicolor) and Groundnut (Arachis Hypogaea) in Acid Tropical Malaysian Peat

Abstract

S U M M A R YIn three field experiments, peat pH increased in parabolic relation to liming at the rate of 0.0544 pH unit/t/ha between 0-40 t/ha lime, but only 0.0224/t/ha between 40-72 t/ha. Groundnut and sorghum seed yield and crop residue also showed parabolic responses to peat pH and liming, but groundnut seed yield correlated poorly with soil pH (r J = 0.38, P=0.05), compared with its crop residue as well as with sorghum seed and residue (r J = 0.75, 0.76 and 0.79, respectively, P= 0.01). Groundnut was generally more tolerant of peat acidity (pH 3.35-3.65) than sorghum, giving higher plant survival in unlimed plots, optimum seed and residue at pH 4.60 compared with 5.70 for sorghum, and reduced responsiveness to pH increase. Seed and residue of both crops decreased with continuous cropping, probably because of increasing pest and disease incidence and depletion of available soil nutrients.

Liming Needs of Sweet Potato in Malaysian Acid Peat

“…Liming to raise soil pH is therefore essential to optimize yields. In these experiments, sweet potato produced optimum tuber and vine DM at pH 5.5 (Figs 4a and b) which is comparable to the pH optima earlier obtained on peat for tobacco (5.25; Chew et al, 1980b) and sorghum (5.7; Chew et al, 1981b), but appreciably higher than for pineapple (pH 3.0-3.5; Tay, 1972) and cassava (3.8; Chew et al, 1980c), while groundnut and guinea grass are intermediate in sensitivity to peat acidity (pH optima 4.6 and 4.2, respectively; Chew et al, 1980c and1981a).…”

“…The lime treatments, quadruplicated in a randomized complete block design in each experiment, were broadcast manually and worked to about 20 cm depth in 12 X 6 m plots, sited on drained peat, newly cleared of primary jungle vegetation and undecomposed wood in the topsoil, which sample analysis showed was similar to that in earlier experiments (Chew et al, 1981a and1981b). Limed plots were made into ridges 1 m apart and about 45 cm high in which leafy terminal sweet potato shoots, each 30 cm long, were planted about 10 cm deep and 20 cm apart.…”

“…Preliminary work on peat in Jalan Kebun suggests that sweet potato (Ipomoea batatas) needs liming. Like cassava (Chew et al, 1981a), it is a very promising root crop for potential wide-scale cultivation on peat, on which it tuberizes unhindered and from which it is easily harvested (Joseph et al). The present experiments were therefore designed to investigate the crop's liming and pH requirements, while further testing its adaptability to acid peat.…”

Laboratory and Field Evaluations of Sorghum for Response to Aluminum and Acid Soil1

“…Plant responses to acid soil mineral stresses are well documented ( 6,8,14,20,28). Sorghum [Sorghum bicolor (L.) Moench] production has extended to many acid soil regions and has received considerable attention relative to the nutritional complexities associated with these soils (5,7,9,13,17).…”