Effect of benzimidazole fungicides and calcium chloride on Alternaria alternata and Penicillium expansum rot during storage of pears

The present study assayed the effect of the fungicides benomyl, methyl-thiophanate, thiabendazole and calcium chloride on fungal decay of pears caused by Alternaria alternata and Penicillium expansum. Both in vitro and in vivo, the efficacy of fungicides alone against the two fungi was shownto be weak and without any practical interest. In vitro, CaCl2 alone was tolerated by both species at more than 4%. In vivo and at low temperature, CaCl2 significantly reduced fungal decay when used at 4 and 6%. The association fungicides - CaCl2 (4%) allowed a better control of A. alternata

Antibacterial effects and toxigenesis of Penicillium aurantiogriseum and P. viridicatum

The toxigenesis of one Penicillium aurantiogriseum and one Penicillium viridicatum isolates was investigated. Sterile culture filtrates of both fungi had a clear antibacterial effect only against Bacillus subtilis. The effect on B. subtilis varied with amount of filtrate used and temperature. The antibacterial activity of chloroform extracts varied with the nature of media used to grow the fungi. Different mycotoxins were identified in the fungal cultures using thin-layer chromatography. P. aurantiogriseumwas found to produce penicillic acid, terrestric acid and aurantiamine, while penicillic acid, terrestric acid, brevianamide A and xanthomegnin were produced by P. viridicatum

Callus Induction from Carob (Ceratonia siliqua L.) Seedlings and Leaves of Mature Tree

Callus induction was successfully carried out from several explants of carob (Ceratonia siliqua L.). Callogenesis from the apex was tested on three different media containing Woody Plant Medium (WPM), Murashige and Skoog (MS) or Schenk and Hildebrandt (SH) macronutrients supplemented with two different hormonal solutions: benzylaminopurine (BAP) at 4.44 µM alone, or 2.22 µM of BAP plus 5 µM of 2-naphthalineacetic acid (NAA). Primary callus formation was obtained on a medium containing 88% WPM macronutrients. Callus formation from other parts of the plant was as follows: − Cotyledon embryos extracted from immature seeds (85% success rate on WPM medium, containing 4.44 µM BAP and 5 µM NAA); − Cotyledon leaves taken from 7-day-old seedlings, obtained from in vitro germination of seeds (62% success rate on WPM medium, containing 4.44 µM BAP and 5 µM NAA); − Hypocotyls taken from 7-day-old seedlings (55% success rate on WPM containing 2.22 µM BAP and 5 µM NAA); − Differentiated leaves taken from mature tree (84% success rate on WPM medium, containing 4.44 µM of BA and 2.26 µM of NAA). In general, production of primary calli and their growth after transplantation was better on WPM medium supplemented with 2.5 µM NAA and 2.22 µM BAP

Micropropagation of Carob tree (Ceratonia siliqua L.) by cotyledonary buds

La micropropagation du Caroubier (Ceratonia siliqua L.) par culture de bourgeons cotylédonaires de plantules âgées de 13 jours a été étudiée sur le milieu WPM additionné de microéléments et de vitamines MS. La comparaison de l’effet de quatre cytokinines (BAP, zéatine, kinétine et 2-iP) a montré que la croissance des pousses est surtout stimulée par la zéatine (1 mg/l) ; alors que l’organogenèse se fait mieux en présence de la BAP ou de la zéatine (1 mg/l). L’effet de quatre auxines (AIA, AIB, ANA et 2,4-D) à faible concentration (0,1 mg/l) combinées à la BAP (0,5 mg/l) a été aussi testé, et a montré que l’ANA favorise la croissance des plantules et la néoformation de tiges. Toutefois, l’association de l’AG3 à différentes concentrations avec la BAP (0,5 mg/l) n’a pas eu d’effet significatif sur la culture de ces explants. La multiplication des pousses a été favorisée par des concentrations moyennes de BAP (0,5 à 1 mg/l) seule ou associée avec l’AG3 (0,2 mg/l). Parmi les auxines testées au cours de la phase d’enracinement, l’AIB (2 mg/l) s’est avéré la plus efficace pour la rhizogenèse.In vitro micropropagation of Carob tree (Ceratonia siliqua L.) by cotyledonary buds taken from 13 day old seedlings was attempted on Woody Plant Medium (WPM) supplemented with microelements and Murashige and Skoog (MS) vitamins. Comparison of the effect of four cytokinines (benzylaminopurine, zeatin, kinetinand 2-iP) has shown that seedling growth was stimulated by zeatin at 1 mg/L, while organogenesis was better under BAP or zeatin at 1 mg/L. The effect of four auxins (AIA, AIB, ANA and 2,4-D) at low concentrations (0.1 mg/L) combined with BAP at 0.5 mg/L has shown that Naphthalene Acetic Acid (NAA) stimulates better stem formation and growth. Moreover, combination of Gibberellic Acid (GA3) at different concentrations with BAP at 0.5 mg/L did not show a significant effect on growth. Shoot multiplication was stimulated by medium concentrations of BAP (0.5 - 1 mg/L) alone or with GA3 at 0.2 mg/L. Among the auxins tested during rooting, Indol-3-Butyric Acid (IBA) (2 mg/L) was found to be the most efficient for root formation

Callus Induction from Carob (Ceratonia siliqua L.) Seedlings and Leaves of Mature Tree

Callus induction was successfully carried out from several explants of carob (Ceratonia siliqua L.). Callogenesis from the apex was tested on three different media containing Woody Plant Medium (WPM), Murashige and Skoog (MS) or Schenk and Hildebrandt (SH) macronutrients supplemented with two different hormonal solutions: benzylaminopurine (BAP) at 4.44 µM alone, or 2.22 µM of BAP plus 5 µM of 2-naphthalineacetic acid (NAA). Primary callus formation was obtained on a medium containing 88% WPM macronutrients. Callus formation from other parts of the plant was as follows: − Cotyledon embryos extracted from immature seeds (85% success rate on WPM medium, containing 4.44 µM BAP and 5 µM NAA); − Cotyledon leaves taken from 7-day-old seedlings, obtained from in vitro germination of seeds (62% success rate on WPM medium, containing 4.44 µM BAP and 5 µM NAA); − Hypocotyls taken from 7-day-old seedlings (55% success rate on WPM containing 2.22 µM BAP and 5 µM NAA); − Differentiated leaves taken from mature tree (84% success rate on WPM medium, containing 4.44 µM of BA and 2.26 µM of NAA). In general, production of primary calli and their growth after transplantation was better on WPM medium supplemented with 2.5 µM NAA and 2.22 µM BAP