Re: [beemonitoring] Prosopis juliflrora question
- Dear Dr Sajjad:If I were you you I would look up the publications from the laboratory of the late, Dr. R. Bruce Knox (School of Botany, U. of Melbourne - Australia) on pollination of Australian Acacia (1979-1989). Unfortunately, these papers are too early for PDF files. When Googling use my name and the name of Dr. J. Kenrick. When we calculated reproductive success in Acacia we used the inflorescence, not the individual floret, for the same reason. A simple inflorescence could contain up to 200 florets. I would also suggest counting the number of inflorescences on a twig or a branch. The trick is having the same definition for twig or branch.Seed set in Acacia may be calculated in several ways. In some cases it is best to collect the following three pieces of data for each population of shrubs.1) Number of pods on a branch/number of original inflorescences on the same branch2) Number of pods on one inflorescence/original number of florets3) Number of seeds in a pod/number of ovules in an ovary.Please write Dr. J. Kenrick jkenrick@..., for additional information.Sincerely, Peter BernhardtDepartment of BiologySaint Louis UniversitySaint Louis Missouri 63103U.S.A.Telephone (office): 314-977-7152On Sat, Oct 29, 2011 at 12:19 PM, Asif Sajjad <asifbinsajjad@...> wrote:
Dear All,I am working on the effect of insect visitors diversity on Prosopis juliflora (Fabaceae) pollination. I need to know what reproductive parameter I should consider e.g seed set, pod weight, flowers that set pods etc. Moreover I am not sure how to calculate %seed set. More than 300 flowers are arranged in a raceme.Regards--
Asif SajjadProject CoordinatorWWFJhang, PakistanCell: 0300-6345639Tel: 0477-650725
- Hi Asif,I have worked in coffee pollination and in some sense there are similar challenges because the flowers are crowded in a branch, not in an inflorescence as in your case, but push you to think in kind of similar alternatives. Some ideas that came to my mind were:
1. Since the number of flowers in a raceme is too large (and surely you don't want to count them all in each raceme of your experiment) I would try to see if there is a good-enough correlation between total raceme length and number of flowers per raceme. A friend of mine did something similar in to avoid a long process too - like counting flowers in your case - and it worked. He got a correl. coef higher than 0.9 so he went for that option. If you are lucky too - which I think is highly possible given the related variables - you could be able to measure total raceme length and estimate the number of flowers from that.
2. Based on the 'hopefully good correlation' you could get from above, you could do some pilot pollination experiments to see if there is a bee pollination effect.
3. If you interest behind this experiment is to provide food (the Prosopis pods) for animals - as one of the common uses of Prosopis - I would try to relate the pollination experiments to pod weight.
4. However, after weighting the pods, you can also select just some of them to count seeds too (and why not, test if the pod weight of those subsamples is related with number of seeds per pod). Doing that you will get a measurement of seed set: if the relation between raceme-lenght is good, you will be able to estimate number of flowers from that and relate that number with the number of seeds per raceme
I hope my comments will help you, though they are pretty basic. I know that when one deals with plant species like Propopis, where flowers are crowded in an inflorescence, pollination experiments could be tricky to design.Jaime A. FlorezPhD student
Dept. Biology & Ecology Center. Utah State Univ.
Logan, Utah. USA