Boron deficiency in white clover (Trifolium repensL.) seedlings grown in an organic soil

Abstract

1025In a pot trial using Rukuhia peat, white clover (Trifolium repells L.) seedlings grown without added boron developed distinctive deficiency symptoms. The addition of borax at 20 lb per acre increased the dry matter yield five-fold at the first harvest. This response diminished in subsequent harvests, and after three harvests there was no response in dry matter yield.BOro'l application increased the boron content of the plants at all harvests but it affected the nitrogen content of the plants in the same way as it did dry matter yield. It is concluded that the effect of boron was an indirect one and that it operated through an effect on the nitrogen nutrition of the clovers.A considerable amount of the added boron was rendered insoluble in hot water during the period of the trial.

Boron deficiency and response in white and red clovers and lucerne

“…The stems did not lengthen and a mass of stunted shoots developed at the base of the plant. These symptoms on young leaves are similar to those obtained in white clover seedlings (Sherrell 1966).…”

“…However, there is such exact agreement for the critical range of B concentration in lucerne in this trial and those obtained in field trials and surveys (Sherrell & Toxopeus 1978;Sherrell 1983) that, by analogy, the data obtained here for clovers might also apply to the field.…”

“…There is a similar lack of agreement for white clover. McNaught (1970) considered B concentrations below 25 ppm to indicate response but Sherrell (1966) reported no response when plant concentration was 12-20 ppm B. This lack of agreement may be caused by differences in environmental conditions under which the plants were grown.…”

“…is widespread in New Zealand (Davies 1952) and also occurs in lucerne (Medicago sativa L.) in some areas (During 1972;Sherrell 1983). Clovers (Trifolium spp.)…”

Boron applications to pastures: effect on herbage and soil boron concentrations

“…Unfortunately,criticalBconcentrations in clovers are not welldefined (Martin & Matocha 1973). With white clover, McNaught (1970) considered B concentrations below 25 J.l.g Big to indicate response but Sherrell (1966) reported no response whenplantconcentrations were12-20 J.l.g Big.Similarly,criticalBconcenttationsinredclovers are reported as ranging fromless than 12Ilg Big to 28 Ilg Big (Tucker & Smith 1952;Philipson 1953;Gupta 1984). Sherrell (1983a) suggested that the lack of agreement between different studies was caused by differences in environmental conditions under which theplants were grown.…”