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The need to obtain crop varieties that are tolerant to heat and drought cannot be overemphasised especially with the threat of climate change to agricultural productivity in sub-Saharan Africa. Bambara groundnut has been identified as a drought tolerant crop; however, variations exist among landraces with respect to drought tolerance. An experiment was therefore conducted to evaluate the performance of five bambara groundnut landraces: Black eye, Burkina, NAV 4, NAV Red and Tom, to drought and heat stress, at the Irrigation Company of Upper East Region (ICOUR) at Tono-Navrongo in the Upper East Region of Ghana. The experiment was arranged in a Randomized Complete Block Design with three replicates. The heat trial was irrigated once weekly to field capacity until crop maturity. The drought trial was irrigated once weekly until 30 DAS, after which irrigation ceased. Burkina, a landrace from Burkina Faso produced the highest pod yield of 1.2 t/ha under the heat treatment. Tom did not produce any pod yield. Under drought, Burkina exhibited the greatest root dry weight and leaf area at 120 DAS, and had the longest leaf area duration (LAD). Burkina exhibited bunch canopy architecture, while NAV 4, NAV Red, and Black eye had an intermediate canopy type and Tom a spreading type. Burkina proved the most drought and heat tolerant among the five landraces evaluated. Though a drought tolerant crop, temperatures beyond 38°C and low relative humidity can negatively affect pod yield of bambara groundnut even when irrigation is provided. It is important to test the performance of a crop under a new environment before money is invested into its production in that environment.

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The regrowth of Italian ryegrass following a cut in late April was studied at weekly intervals up to 14 weeks. There were four levels of applied N: 28, 84, 140 and 196 kg ha"'. The proportion of green leaf blade declined from 80% of DM yield after 2 or 3 weeks of regrowth to 5% after 13-14 weeks. About three-quarters of the increase in DM yield of total herbage from week 3 to week 11 was attributable to increased yield of 'stem'. The level of applied N had little efFect on the proportion of crop fractions except during the period immediately before and after the begiiming of ear emergence when the higher rates of N increased the proportion of 'stem' and reduced that of green leaf. The most digestible crop fractions were green leaf, inflorescence and immature 'stem'. D-value of 'stem' declined by about 20 units from week 1 to week 14, while D-value of green and dead leaf declined at about half this rate and there was little or no decline in D-value of inflorescence. The N content of green leaf was consistently higher than that of the other fractions. The N content of 'stem' declined markedly to around 0-5% by week 12. The N content of dead leaf and inflorescence was intermediate between that of green leaf and mature 'stem'. The N content of all fractions was increased by applying more N. The tiller population increased during the flrst 3 weeks of regrowth and declined