Variation in seed morphometric characters, oil content and azadirachtin content of seeds, in vitro shoot cultures and callus cultures among different populations of Azadirachta indica

We studied seed morphometric characters, oil content and azadirachtin content in a medicinally important and insect repellent tree species Azadirachta indica A.Juss. Ten populations were selected from two central Indian states of Madhya Pradesh and Chhattisgarh and twenty candidate plus trees were selected from each population based on tree attributes. Azadirachtin content was estimated in seeds, in vitro shoots and callus cultures through HPLC. Significant variation（p ／ 0.05） was observed in seed morphometric characters, oil content and azadirachtin content among the ten populations. Maximum value for 100 seed weight was obtained in seeds of Raigarh（30.51 g） which was on par with seeds of Bargi（28.37 g）and Chhatarpur（26.36 g）. The ratio of highest kernel to seed was also obtained in seeds of Raigarh（60.11%）.Kernels from Chhatarpur population recorded the highest oil content（24.20%）, which was equal to that in Sihore（23.75%） and Katni（21.75%）. We recorded highly significant variation in azadirachtin content in seed samples,in vitro shoot samples and callus cultures. Maximum azadirachtin was present in the seeds of Gwalior（0.882%）which was on par with azadirachtin content in seeds of Chhatarpur, Katni, Sihore, Shahdol and Chhindwara.Maximum azadirachtin in the in vitro shoots was present in the cultures of Gwalior（0.218%） which was statistically on par with Sihore（0.176%）. Similarly, in callus cultures of nodal segments maximum azadirachtin was recorded in the Gwalior population（0.033%） which was statistically on par with Sihore（0.028%）. The trees of Gwalior and Sihore populations can be produced in large numbers through vegetative propagation to obtain seeds with higher azadirachtin content.

Distribution and morphometric characters of the Mediterranean longnosed skate,Dipturus oxyrinchus(Chondrichthyans:Rajidae)in the Gulf of Gabes(Tunisia,Central Mediterranean)

Objective:To investigate biometrics of Dipturus oxyrinchus(D.oxyrinchus),including length-weight relationships,total length(TL),disc width(DW),distance measured of snout tip to eye,width of the mouth,distance from snout tip to first dorsal,and the numeric characters in the Gulf of Gabes.Methods:Monthly sampling was conducted commercial bottom-trawl during December 2006 and January 2007,operating at a depth of 80-185 m.The TL,DW,distance of snout tip to eye,width of the mouth,distance from snout tip to first dorsal were measured to the nearest 0.1 cm and the weight was measured to the nearest 0.1 g.The parameters a and b were estimated by the least squares regression method.Results:A total of 520 D.oxyrinchus was ranged from 16.5 to 105.0 cm in TL and 30-5300 g in total mass were analyzed during this study.The overall sex ratio was significantly different from the expected value of 1:16(df=1,χ^(2)=3.38,P<0.05),and there was significant difference in the TL(t-test=16.53,df=520,P<0.05).There was significant difference in the regression slopes between sexes for the TL and DW relationship(t-test=17.53,df=520,P<0.05).The b value for the TL/weight relationship for males D.oxyrinchus sampled in this study(3.01)was lower than that for female(3.23).Morphometric characters were strongly positively correlated for TL.Conclusions:This study reported the first description of biometric relationships for D.oxyrinchus,which would be useful for the sustainable conservation of this rear fishery in the Gulf of Gabes and also form the basis for their inclusion in a regional security programme.