The South Pacific region represents a large potential genetic resource for improvement of coconut palms (Cocos nucifera L.). A study of the genetic diversity in the species was made in 1992–1993 by means of RAPD analysis on a representative sample from 17 distinct South Pacific coconut populations to characterize the germplasm present in the region. A moderate level of genetic diversity was found, although very few RAPD markers were unique to specific populations. Approximately 60% of the observed diversity occurred within‐populations, but this level varied between the various populations. This indicated the generally low but variable influence of gene migration between populations, the establishment of populations by few individuals that comprised a fraction of the genetic variation of their parental populations (founder effects), and subsequent selection by the local human population. Although the coconut populations of the region generally displayed a pattern of continuous variation, this continuum could be divided into discrete groups by cluster analysis. This division comprised a southern group of populations, a northern‐eastern group, and singlepopulation groups from the Marquesas and Hawaii groups. The population from Rennell Island diverged from the main genetic continuum, apparently because of isolation and artificial selection. Collection and conservation strategies have been devised for coconut germplasm in the South Pacific region based on existing genetic diversity.

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Controlled temperature conditions were used to investigate the chilling requirements of potted 1-year-old apple trees cv. Jonathan. The rate of bud break, the number of buds growing and extension growth were increased by prior chilling. Temperature effects over the range 2–10°C were greatest at the lower end of the range. Chilling early in the dormant period was less effective than later chilling, and interruption of chilling with periods of high temperature reduced subsequent growth.

Tall Coconut Palms Cocos nucifera L. on the Gazelle Peninsula of Papua New Guinea are almost exclusively (96.3%) insect pollinated. Pollination is most likely to occur in the late afternoon when the number of insect visitors to pistillate flowers increases. Two species of halictid bees, Homalictus cassiaef/oris and H. dampieri, are most likely responsible for most of the pollination. On Gazelle Peninsula Coconut Palms, the pistillate receptive phase partially overlaps with the staminate phase in the subsequently produced inflorescence, and on average 27.8% of fruits are a result of self-fertilization, indicating a mixed breeding system. The self-fertilization rate varies between individuals and with time of the year, and is related to the degree of fertile staminate and pistil ate phase overlap between inflorescences. The flexibility in the breeding system appears to confer potential adaptive flexibility on Coconut Palms because they are able to self-pollinate if individuals become established in areas devoid of other Coconut Palms.

Apple and peach seedlings were grown for 8 weeks under various regimes: two photoperiods (16 and 8 hr), two air temperatures (12.8° and 18.3°C) and three root temperatures (12.8°, 18.3° and 23.9°C). After the leaves were removed the seedlings were chilled in the dark at 5.6° for three periods (apples 750, 1500 and 2500 hr; peaches 750, 1500 and 2000 hr) and then grown in a glasshouse for 7 weeks during which bud break and extension growth were measured. Growth of apple seedlings (cv. Granny Smith) stopped in an air temperature of 12.8� irrespective of photoperiod and root temperature. At 18.3° growth continued, but was retarded by short days and a root temperature of 12.8°. Peach seedlings (cv. Elberta) did not grow after any of the treatments. Extension growth and bud break in both species increased with increased hours of chilling. Pre-dormancy factors had no effect on bud break in apples, but low air temperature and short days prior to chilling increased bud break in peaches, although the effects decreased as chilling increased. Low pre-dormancy air temperature increased the growth of both species after chilling. Photoperiod produced opposite effects in the two species. Thus short days increased the growth of peaches while long days were effective with apples. Apples grew best at a root temperature of 12.8°, and peaches grew better at this temperature than at 18.3° but not as well as at 23.9°.