Evaluation of clovers in dry hill country 9. White clover at “Ballantrae”, and in central Wairarapa, New Zealand

Abstract

Herbage production, vegetative persistence, and seedlingregeneration of 10 white clover (Trifolium repens L.) lines were evaluated on a steep, dry hillside at Ballantrae Hill Country ResearchStation,and at a drought-prone site in the central Wairarapa, New Zealand. New Zealandbred lines produced more herbage than overseas linesin bothmeasurement years (1982/83 and 1983/ 84)atBallantrae, andin thefirstof twomeasurement years at the Wairarapa site. Production of most lines increased between 1982/83 and 1983/84 at Ballantrae; 'Hill Country' selection showed the greatest increase (from 240 to 715 kg dry matter (DM)/ha per year).Severedroughtat theWairarapa site during early 1983 depressed mean clover production by 23% in 1983/84 comparedwith the previous year, and altered the relative ranking of lines. 'Tamar' and 'Louisiana Sl' emerged as the most productive lines after the drought, though contamination by resident clover probably contributed heavily to measured herbage yields in thesetwocultivars. Recoveryof the stolonmaterial which survived drought appeared to play a large role in re-establishing white clover populations at the Wairarapa site. Seedlings of all genotypes were observed in 1982 and 1983 at both sites, but they had little impact on subsequent herbage accumulation or stolondensity.

Phenological development of subterranean clover cultivars under contrasting environments

“…The knowledge of cultivar maturity and establishment enable estimations of the chronological time available to defoliate subterranean clover plants after seedlings had accumulated ~434°Cd (Figure 9) from emergence to five trifoliate leaves stage (Moot et al, 2003) . The earliest the subterranean clover establishment, for example in late summer, the highest chances of weed suppression due to faster canopy closure (Teixeira, Lucas, Lewis, & Moot, 2017) and the longest the defoliation period available before plants shift to reproductive stage (Chapman & Williams, 1990). Defoliation events can also be targeted between the fifth trifoliate leaf (V7, ~ BBHC stage 15) and runner extension (VR, BBHC stage 30) phases without impacting on the reproductive phase (R1, BBHC stage 50).…”