Die invloed van stikstoftoediening, saaidigtheid en metode van vermenging van komponente op mengsels van Trifolium vesiculosum en Lolium multiflorum¹

Deel van ‘n verhandeling vir ‘n M.Sc.(Agric.) graad, Universiteit van Pretoria

Abstract

The influence of nitrogen application, seeding rate and methods of mixing of components on mixtures of Trifolium vesiculosum and Lolium multiflorum. The interaction between Trifolium vesiculosum cv. Amclo and Lolium multiflorum cv. Midmar in mixtures was measured in an irrigated field trial in terms of dry matter production, crude protein content and crude protein production. Two methods of mixing, namely mixing of the components in the same row and alternate rows of the two species, were compared at two nitrogen levels and three seeding rates of the grass component. The method of mixing and seeding of the grass had little effect on dry matter production. On the other hand, the application of 240 kg N ha⁻¹ increased the dry matter production of the different mixtures significantly, but at the same time changed the botanical composition drastically owing to the suppression of the clover component. The weighted crude protein content of the mixtures were significantly higher where 240 kg N ha⁻¹ was applied owing to a positive response of both the grass and the clover to nitrogen. Generally speaking, crude protein production followed dry matter production closely.

Die wisselwerking tussen Trifolium vesiculosum cv. Amclo en Lolium multiflorum cv. Midmar in mengsels is in terme van droëmassaproduksie, ruproteïeninhoud en ruproteïenproduksie in ‘n besproeide veldproef gemeet. Twee vermeng‐ingsmetodes, naamlik vermenging van die komponente binne die ry en alternatiewe rye van die twee spesies, is by twee stikstofpeile en drie saaidigthede van die graskomponent vergelyk. Die metode van vermenging en saaidigtheid van die gras het min invloed op die totale droëmassaproduksie gehad. Daarenteen het ‘n toediening van 240 kg N ha⁻¹ die droëmassaproduksie van die verskillende mengsels betekenisvol verhoog, maar terselfdertyd die botaniese same‐stelling drasties verander as gevolg van onderdrukking van die klawerkomponent. Die geweegde ruproteïeninhoud van die mengsels was betekenisvol hoër waar 240 kg N ha⁻¹ toegedien is aangesien beide die gras en klawerkomponente van die mengsels op stikstofbemesting gereageer het. Ruproteïenproduksie het grootliks soos droëmassaproduksie op die verskillende behandelings gereageer.

Additional index words:

• Competition
• interaction

Notes

Deel van ‘n verhandeling vir ‘n M.Sc.(Agric.) graad, Universiteit van Pretoria