Aspects of the phosphorus nutrition of white clover populations. V partitioning of dry matter

Abstract

The partitioning of dry matter into leaf, stolon and root varies between populations of white clover, and may partially explain differences in survival of populations under sustained intense grazing. The stoloniferous habit of white clover may explain its success, compared with other herbage legumes, in grazed swards. Plant nutrient status influences the partitioning of dry matter.

The present study examined the effect of phosphorus (P) supply and P‐status of plant material on partitioning of dry matter between green leaf, dead leaf, stolon and root of six white clover populations. Larger leaved populations had a higher proportion of green leaf and a lower proportion of stolon than small leaved populations. Plants of high P‐status maintained the same proportions of green leaf and stolon for some time after withdrawal of P supply. When P was supplied to P deficient plants, the proportion of green leaf increased rapidly while proportions of stolon and dead leaf decreased. There was no interaction between plant P status and P supply for proportion of root.

There were significant interactions between population and P supply for the proportions of green leaf, dead leaf, stolon and root. However, there was no evidence that populations differed in their ability to respond adaptively to the onset of P deficiency, or recovery from P deficiency, by varying the partitioning of dry matter between leaf, stolon and root.

Key Words:

• White clover
• harvest index
• populations
• phosphorus
• solution culture

Notes

Grasslands Division, DSIR, Private Bag, Palmerston North, New Zealand.