Evaluation of Protein Concentration, Amino Acid Profile and Antinutritional Compounds in Hempseed Meal from Dioecious and Monoecious Varieties

Hempseed meal from three dioecious and three monoecious varieties has been evaluated for content and quality of the protein and for the concentration of antinutritional compounds. Hemp seeds were obtained from plants grown in two experimental fields for two consecutive years (2011-2012). For all the varieties, hempseed meal resulted in a rich source of protein (34% mean content) with an amino acid profile extremely rich in arginine and slightly poor in lysine. Differences between dioecious and monoecious varieties were observed in the content of antinutritional compounds. They were more concentrated in monoecious varieties in comparison with those dioecious. The concentration of phytic acid in hempseed meal deserves attention in both groups, being 63 and 75.4 g·kg-1 of dry matter in dioecious and monocieous varieties, respectively. The results show that, besides the recognized value of hemp oil, also the hempseed cake could find application in animal feed as a substitute of other cakes (soybean, rapeseed). From this point of view, the dioecious varieties showing lower contents of antinutritional compounds with respect to the monoecious varieties would be preferred.

Zoospore-derived monoecious gametophytes in Undaria pinnatifida(Phaeophyceae)

The annual life cycle of the brown seaweed Undariapinnatifida （Harvey） Suringer comprises a macroscopic diploid sporophyte stage and a microscopic haploid gametophyte stage. In 2011, an unusual zoospore-derived monoecious gametophyte isolate （designated as line 10-5-3） of U. pinnatifida was observed. To understand this phenomenon, a comprehensive screening of eighty-two previously identified male gametophyte cultures, isolated from three randomly selected cultivars （lines 10, 7, and 5） was performed. Thirty-six of the isolates developed both antheridia and oogonia on the same filamentous fragment in a standard gametogenesis test （SGT： 18℃, 60 umol photons/（m2.s））. Selfing of the monoecious gametophyte or crossing it with a normal male gametophyte both gave rise to morphologically normal sporophytic offspring. However, crossing resulted in a much higher fertilization rate （89.7%）. The hybrid and selfed sporophytic offspring were grown to maturity in flow tanks at an ambient temperature of 10-18℃ over a period of 69 days. Active zoospores were released from both types of mature sporophylls. The majority of these developed into male gametophytes, while 15%-20% developed into the observed monoecious structures on the same filament. Using PCR amplification it was found that all the monoecious gametophyte isolates and the sporophytic offspring resulting from the selfing and crossing lacked the femalelinked microsatellite sequence （a part of the locus Up-AC-2A8, GenBank accession No. AY738602.1）, indicating their male nature. U.pinnatifida is an invasive species in some regions and the implications of the above findings for this species in nature are briefly discussed.

Morphological Characterization and Phenological Modeling of <i>Jatropha platyphylla</i>(Euphorbiaceae) Muell. Arg. Genotypes

Morphological characterization and phenological modeling were carried out on genotypes of Jatropha platyphylla collected from the states of Sinaloa and Durango, Mexico. The morphological characterization evidenced the existence of monoecious plants, finding individuals with male and female flowers in the same inflorescence. Fruit with four seeds was also found. The phenological study was divided into two phases and calculated in thermal requirement (°D): Vegetative [seedtime (0), germination (24), emergence (98), cotyledons (87), second (302) and fourth (524) true leaves, end of vegetative growth (302)] and reproductive [flowering (303), fructification (342), maturation (126), defoliation and senescence (450)]. The thermal constant (2558) was similar in all eight genotypes. The phenological stages and the accumulated degree days were adjusted with a third-degree polynomial (Stage = -0.0041x3 + 0.7446x2 - 8.6808x + 6.2448) (R2 = 0.99%) stage. The development of phenological models facilitates the prediction of the flowering date for the selection of varieties with high oil and protein content.

Seed and Wasp Production in the Mutualism of Figs and Fig Wasps

Figs (Moracea: Ficus) and fig wasps (Hymenoptera: Chlocloids: Agaonideae) depend on each other to complete their reproduction. Monoecious fig species and their pollinating wasps are in conflict over the use of fig ovaries which can either produce one seed or one wasp. From observation on Ficus virens Ait., we showed that female flowers with outer layer of ovaries (near to the wall of syconium) had no significant difference from that with inner and interval layer of ovaries (near to the syconium cavity), in which most seeds and wasps were produced. This meant that fig tree provided the same potential resource for seed and wasps production. Observation indicated that there was usually only one foundress in syconium at female flower phase and no com- petition pollinators. Measurement of the style length of female flowers and the ovipositor of pollinators indicated that most ovaries could be reached by pollinator’s ovipositor. However, at the male flower phase, production of seeds was significantly more than that of wasps including non-pollinating wasps but there was no significant difference between seed and pollinating wasp production when without non-pollinating wasps produced. This result indicated that non-pollinating wasps competed ovaries not with seeds but with pollinating wasps for ovipositing. Bagged experiment showed that the sampling fig species was not self-sterile which was important for figs and wasps to survive bad season. Seed production in self-pollinated figs was not significantly different from total wasps in- cluding non-pollinating ones. This might be related with the weaker competition among wasps since bagged figs were not easy to reach by wasps from outside.

Gender plasticity uncovers multiple sexual morphs in natural populations of Cedrus deodara (Roxb.) G. Don

Background:The expression of gender in gymnosperms is challenging because the extent of variability in gender segregations in tree crowns and selection pressure of nature can modify the gender through time.Methods:An in-depth investigation on spatial segregation of genders in tree crowns and sex expression of a total of 500 trees in five different natural populations of Cedrus deodara was carried out and verified the occurrence of subdioecious(co-existence of male,female,and monoecious)genders in C.deodara.Results:Five different sexual morphs were apparent among the 500 selected individuals as(1)pure male(M):bearing only male strobili in the whole crown with 22.2%;(2)pure female(F):bearing only female strobili in the whole crown with 12.4%;(3)mixed-monoecious(MM):bearing both male and female strobili with 13.6%;(4)predominantly female(PF)with 25.6%;and(5)predominantly male(PM)with 26.2%.The occurrence of multiple sexual morphs resulted from the complex selection pressure,which increased the stability of the populations.The segregation of genders in crown layers deemed to increase the fitness that may be a mechanism for accelerating outcrossing.The results of the study suggest that the subdioecious gender expression in C.deodara is evolved through the monoecy–paradioecy pathway.The production of male strobili revealed non-significant effect of tree sizes whereas a significant effect was observed for the production of female strobili.Our study established that the total pollen and seed outputs in C.deodara changed frequently according to gender expression.Conclusions:The size of the tree,resource availability,sex allocation,plant architecture,gender segregation in crowns,and habitat conditions are the prominent causes for gender plasticity.