Performances of juveniles are a key process for the existence of species in the community. Effect of topography, crowding effect and forest regeneration cycle, and conspecific plants in the context of Janzen-Connell hypothesis on height growth rate of seven major tree species were evaluated based on measurement of juveniles for nine-year period in a 1-ha plot of a tropical rain forest in West Sumatra, Indonesia. Height growth rate was significantly smaller in Calophyllum soulattri than other six species, and the latter species had approximately equivalent height growth rate. Growth rate was positively correlated with initial height in five species, but was negatively correlated in Calophyllum soulattri. Negative effect of conspecific juvenile density was detected by regression analysis only in Calophyllum soulattri. Topography was significant in two species (Hopea dryobalanoides and Mastixia trichotoma). Negative effects of total basal area including all species was found in one species (Swintonia schwenkii). Negative effects by conspecific plants was not dominant at least for height growth rate. Calophyllum soulattri was the only exception showing different behavior from the other species studied.

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A Field experiment was conducted at Research Farm, Chaudhary Charan Singh Haryana Agricultural University, Hisar, during the kharif seasons of 2004 and 2005 to find out suitable spacing for pearlmillet hybrids along with nitrogen and phosphorus levels to increase the productivity and quality of pearlmillet. The experiment was laid out in split plot design allocating two hybrids and three plant densities in main plots and four fertility levels in sub plots replicated thrice. Highest grain yield (35.3 q/ha) was recorded when the crop was sown at a spacing of 45 &time; 12 cm and fertilized with 90 kg N + 45 kg P₂O₅ ha^-1 but was at par with 60 kg N + 30 kg P₂O₅ ha^-1. Pearlmillet HHB 67-2 recorded relatively higher value for consumptive water used and water use efficiency. This hybrid also fetched highest protein yield. Wider spacing (60 &time; 12 cm) resulted significantly higher protein content over closer spacing but 45 &time; 15 cm spacing resulted into higher protein yield. Further higher protein yield was harvested when the crop was fertilized with 90 kg N + 45 kg P₂O₅ ha^-1.

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We quantified the reestablishment of rattans (climbing palms) after severe forest fires in 1997-1998 caused by the El Niño Southern Oscillation event in Bukit Bangkirai, East Kalimantan, Borneo. We established a 1-ha study plot in unburned forest (K1) and two 1-ha plots in burned forest (LD2 and HD2, 200 and 800 m away from unburned forest, respectively). In 2006 the number of species and stem density of rattans including seedlings were 16 and 8 species ha^-1 and 88 and 24 stems ha^-1 in LD2, and HD2, respectively. These values were lower than those in K1, where 23 species and 3321 stems were recorded. The dominant species in burned plots were Ceratolobus concolor, Korthalsia debilis, and Plectocomiopsis geminiflora, which were minor components in the unburned plot. Rattans likely recolonized burned forest sites by seeds transferred from neighboring unburned forest by birds and animals. The distance from unburned forest appeared to affect the speed of the recovery in the burned plots. Although recovery of the stem density of rattans was slower than that of trees in burned plots, it will likely increase gradually because the number of recruits consistently exceeded mortality during our study period (February 2006 to August 2007). However, it is not clear whether species composition and the density in burned forests recover to preburned levels.

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To better understand the effects of light and salinity on the gas exchange and morphological features of mangrove trees, we examined seedlings of Avicennia alba Bl. and Bruguiera gymnorrhiza (L.) Lamk. Seedlings of the two species were cultivated at three light levels (100%, 50%, and 20% sunlight) and five salinity levels (0, 10, 20, 30, and 40 ppt). Changes in characteristics of gas exchange (maximum gross photosynthetic rate, stomatal conductance, transpiration rate, dark respiration rate, and water use efficiency) and leaf morphology (anatomy, specific leaf area, and leaf porosity) were recorded and analyzed. Gas exchange characteristics and leaf morphological features of A. alba were affected mainly by light environments and less by salinity levels, whereas those of B. gymnorrhiza were affected by both light environments and salinity levels. This can support a wider range of salt tolerance of A. alba. For A. alba, almost all gas exchange characteristics were lower at a salinity of 0 ppt (fresh water) compared to other salinity levels, whereas those of B. gymnorrhiza were not. The leaves of B. gymnorrhiza under high relative light intensity were thicker than under low relative light intensity due to increases in both palisade and spongy layer thickness. In contrast, A. alba leaves showed increased palisade layer thickness without changing leaf thickness under high relative light intensity.

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We studied flowering and fruiting seasonality of understory shrubs of genus Medinilla (Melastomataceae) in the lower montane forest on Mount Kinabalu, Borneo, in relation to seasonal change in air temperature, rainfall, and solar radiation. Eight sympatric species showed either annual or biannual patterns. The number of species bearing flower buds and flowers increased biannually, indicating that two seasons were favorable for flower budding and flowering of Medinilla species. Individuals of most species started flower budding during January-March, showing strongly negative correlations with seasonal patterns of mean or minimum air temperature in previous a few weeks. The number of fruiting species peaked during May-August and increased when air temperature and solar radiation were high. These findings suggested that flowering activity of most Medinilla species may be regulated by seasonality of air temperature through floral initiation stimulated by low temperature. In addition, the high fruiting activity during period with high temperature and insolation indicated that such climatic conditions may facilitate the development of fruits and seeds of understory plants growing in cool and poor-light conditions, because photosynthesis and other physiological reactions are activated to produce compounds necessary for the development of fruits and seeds.

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