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The once sustainable agroforestry system in the Sudano-Sahelian zone of Cameroon has been abandoned and trees overexploited. A study on the variability in seed and seedling traits of Faidherbia albida (DEL.) A. Chev populations from different climatic zones was carried out. Six populations were selected from Sudanian (Poli, Garoua III, and Figuil) and Sahelian (Yagoua, Moulvoudaye and Maroua I) climatic zones and harvested seeds were transported to the experimental farm of IRAD Yagoua for pretreatment and growth experiment. Four pretreatments (98% sulfuric acid, hot water, scarification and soaking in water for 24 hours) were used to initiate the germination. After one month, the rate of germination (%) was recorded and seedlings were transplanted in three substrates for seedling growth evaluation. Growth traits (Survival, plant height, root collar diameter, number of leaves, root length, plant fresh weight and plant dry weight) were measured after three months. The experimental design was a single tree plot randomized complete block design with 30 blocks. Results indicated there was significant difference (p = 0.002) among pre-treatments for the germination. The highest rate of germination was recorded with seedlings from scarified seeds (78.33%), followed by those from seeds treated with sulfuric acid (76.67%). Seeds and seedling traits were significant among populations with Yagoua recording the highest in most of the traits measured. Scarification can assist in seed germination and movement of seeds between populations and climatic zones should be considered during conservation programs.

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Genetic material originating from contrasting European chestnut (Castanea sativa) populations of Greece, Italy and Spain was evaluated in a common garden test situated in Greece. The aim of the study is to device an appropriate selection strategy by identifying and conserving superior genotypes for current and future use in breeding programs. Breeding material consisted of 143 openpollinated families growing in a common garden provenance-progeny experimental trial. Growth trait genetic parameters were estimated and response to selection was evaluated using family, within family and combined selection methods. Two models were employed for the estimation of family variance and genetic parameters. The CVA varied between 12.1% and 67% among traits and models, showing an increasing trend with age. Heritability estimates were high; however their variation with age was irregular. Selection of superior families regarding three years of measurement for height, diameter, volume index and number of leaves showed a potential gain of 12%-25%, 12%-28%, 33%-73% and 21%-49% over the mean of all plants. Genetic gain for volume index was the highest among the traits studied and the joint model used presented a more effective selection strategy. Results indicate that the experimental trial studied presented substantial genetic variation and sufficient genetic gain opportunities for quantitative traits of economic importance. These findings suggest that inferior trees can be rogued from the experimental trial and a seedling seed orchard of Castanea sativa in Greece can be established.

Sprouted buds of eight mature plus-trees of Castanea sativa were collected from two natural populations (Mt. Paiko and Mt. Hortiatis, Greece). Explants were cultured on Murashige and Skoog (MS) medium (three concentrations of macro and micro-elements) combined with three concentrations of BAP (6-Benzylaminopurine). Results were evaluated based on three multiplication traits: (a) number of shoots produced, (b) length of the longest shoot segments and (c) percentage of responsive explants. A high genotype-dependant variation for the number of shoots produced per explant was detected. MS medium at full salt strength and 0.2 mg l-1 BAP provided the best results based on the multiplication traits measured. Elite mature tree P-2 proved to be highly favourable for multiplication. Rooting was attempted on ½ MS medium at five different NAA concentrations.  Successful rooting (56%) was obtained by using 0.50 mg l-1 NAA in vermiculite medium after eight weeks. These results indicate that the P-2 genotype can be micropropagated from the protocol developed for ornamental purposes, clonal testing and tree improvement applications.Â