I had just finished doing another survey of the animals that live in the whole tomato garden and I got these results
Spider – 1 / 29 plants
Whitefly – 432 / 4 plants surveyed
Thrips – 17 / 4 plants surveyed
Wasp – 1 / 29 plants
Ladybird beetle – 0 / 4 plants surveyed
Leaf Curl Damaged – 6 plants
Plants with leaves affected by white spots – Thrips damage – 4 plants
Leaf Hopper burns – 1 plant only 5 leaves where damaged
Tomato Blossom End Rot – 4 plants had fruits with this problem
I compared these results with data I had collected on week 5 and observations done on week 7 and week 2. I plotted them together with my current data this was the curve plotted thru the use of excel.
It seems as when the plants grew older they started to also accumulate more white flies. The ladybird population also became zero at certain point between week 7 and 15 they may have gone else where for food.
September 25, 2008
I finished doing most of the adjustment on the plant ecology journal. I went back and re-examined my data on plant height and plotted the change in tomato plant height using excel and a little slope assignment for the missing height data and I came up with this graph.
Week 13 was spent most of the time doing a lot of reading and note taking for the animal dissection journal. I began to wonder how similar does the internal structure of my american cockroach is to a german cockroach so I went in search of german cockroaches. I immediately noticed that they where easier to find than the american cockroach just a bit more tricky to catch. I took two samples. And opened them up.
They have the same structure and even have better looking internal organs than my american cockroach.
The body fat is also coloured white and is partially soluble in alcohol. I also noticed that they don't stink as much as my american roaches or perhaps I was maybe lucky enough to have obtained samples that didn't stink.
We can see the pharynx, oesophagus, crop, gastric caeca, ventriculus, malpighian tubules, colon and rectum in this sample. The only thing that was quite obvious when I did this dissection was the degree of difficulty making the ventral cuts on the abodmen since the sample was only around 1.5 cm long. Perhaps the german cockroach would make a suitable test subject for anyone doing studies on cockroaches since they need a relatively low space for their habitat.
I did a tally of the number of fruits per each plant. There are 29 plants all in all. As of the 15th week we have a total of 849 unripe fruits and 113 ripe fruits so a total of around 962 fruits are present for the 29 plants.
Of the 34 plants I noticed that even those plants who where affected by the yellow leaf curl virus still managed to carry their fruit to term the data from the sick plants show that there are 3-8 fruits for the sick plants.
This was the first harvest for the 29 plants in the tomato plot when I weighed them it was around 4.48 kg in total weight. So each fruit has an average weight of 154 grams.
I decided to check out the number of seeds present per fruit. I took 10 samples at random from the pile of 962 fruits that was harvested from the tomato plants. I cut the fruits in half and start to do a count of the number of seeds.
Seed Count Data Set
53 60 54 62 83
64 33 70 28 68
Data from the seed count tells me that there is an average of 57 seeds in one fruit this has a standard error of around 5 seeds. If I used the average number of seeds from the count I did and multiplied it by 962 I would come up with 54,834 seeds for the whole 4.48 kg harvest and it is only coming from 29 trees.
I also noticed that there are only 2 out of 10 fruits which are 3 lobe fruits. So that gives us a probability of 80% that the harvested fruit will have two lobes and 20 % that it is 3 lobe fruit.
The immense number of seeds produced by the plant may indicate that it is the certain kind of plant that may end up as food for animals since it has a huge number of offspring in order to perpetuate the species.
I have been doing a lot of work on the dissection journal for the past four weeks. The original dissection subjects I used where my american cockroaches. I had read somewhere that these animals needed to exposed to CO2 to put them to sleep and make it more manageable. I decided to use the house hold refrigerator. I placed my subject in the blue box and sent them to slumber in the refrigerator.
I then removed the roach from the refrigerator unit and found my specimen stiff and hard. So I decided to reanimate it using hot water and a heating pad.
Once the animal was heated and seemed tender enough to use for the activity I noticed that its antenna was moving and feet were also kicking. So I decided to finally mount it on the cork board in fear that it may recover. These animals are really amazing.
For the first dissection I made I decided to go and look at the digestive tract of the animal and any other structures present. I actually tried to cut the body at the middle. The problem was that I had damaged one of the organs. So I had to repeat the same procedure on my second dissection.
The second dissection went well I got another specimen and had cut the exoskeleton at the one side but I didn't do the other this was another problem since the fats tend to cling to the attached portion. I could now I dentify the organs and they werent damaged. But the smell from the first and second dissection was really bad like fish gone bad. I had to dowse the speciment in alcohol to reduce the stench.
My new problem with the second dissection was that I had not seen the respiratory, circulatory and nervous structures. I tried to look at other resources from the net and found that some readings said that I could go in dorsally or ventrally it depends on what I would like to see.
Third Dissection Week 12
I decided to do my third dissection dorsally and I followed the same procedures and still saw that the roach moving even after 15 minutes in the freezer. The picture below is the dorsal dissection of the american cockroach.
I found it easier to do the positioning of the scissors for the dorsal cut. When I had cut the middle of the dorsal section of the cockroach the crop just went out thru its back. I had to hurry up and cut a larger portion or risk damaging the organ when it gets squeezed.
The organs where exposed easily than in the ventral dissection but I realized that the nervous fibres and respiratory system resides in the dorsal section.
So my efforts were all for nothing. I decided to make some more research for the dissection methods to expose the systems of interest to me.
I started doing the write up for the dissection manual after the second botched dissection and had researched that digestive system of the cockroach is also called the ailmentary canal. It consists of the saliva ducts and glands, mouth, oesophagus, crop (gizzard) , proventriculus(grinder), gastric caeca(enzyme producer), ventriculus (Stomach), colon (Water retention) and rectum (waste disposal).
I also tried to look at my previous samples and found out that most of the tissue of the first and second dissected specimens had shrunk apparently like us roaches also are composed of water. The stink from the samples was far worse than that of the newly dissected sample. So I guess that all the labeling work and drawing should be done directly after the dissection.
I also noticed that proventriculus is the only bulge on the dried up specimen.
After a long wait the fruits have finally ripened so it takes 14 weeks for the whole cycle of life in a tomato to restart. It takes 8-9 weeks for the plants to develop the fruits and another 5-6 weeks for the fruits to ripen and be ready to disperse its seeds. In one of the blog entries for the plant journal I have managed to dissect a tomato fruit and I had asked why it had the jelly stuff around the seeds I now realize that this could serve as buffer between the seed and the enviroment such as the gut of an animal.
The tomato plants are now around 167 cm to 200 cm high. These plants are still growing despite bearing fruit. Notice that in the second picture the plants at the end near the shed have grown higher than the rest. What I noticed is that in the morning these plants had beed shaded by the shed roof they only recieved light of equal amount to the rest of the plants at around 9-10 am. It seems that this has triggered the growth of the plant to go into over drive compared to the others.
In the week 13 I also managed to look at yellow leaf curl problem. I noticed that the curling problem could be related to an enlargement of the vascular tissues of the leaf. A normal leaf has the transport tissues of around 0.5 - 1 mm in affected tissues it is around 2 - 2.5 mm in diameter so there could be an abnormality introduced by the virus on the leaf. I tried to look at the normal leaf and diseased leave with a 100x and 450x microscope I managed to borrow from the microbiology lab at work. But it seemed to be the same. I also noticed that some of the plants that have been affected have gotten better.
Un-opened flower bud.
This next picture is a flower cut in half. It reveals a symmetrical pattern. Note that there is the presence of separate sepals and petals. The stamen (at the middle looks like a yellow petal) is located beside the pistil. So the flower is a complete flower since there are male and female parts present.
I decided to remove the female part and I found it to be inside the sepal. This could be the reason why the blossom still is connected to the growing fruit even at three weeks from the time it blossomed. Since the growing fruit would tend to push the withered blossoms down and outward. It would also explain why the flower points downward since if it where upward then the vascular connection could be stressed further by twisting it.
I noticed that the remaining fruit with the blossom end rot had actually began to ripen. But the other fruits still remained unripe. I believe that the problem may have triggered this ripening but I wont be quite sure without additional materials.
Most of the insects that made the plant their home settled on the leaves of the plant typically under the leaf and if the leaf was shriveled they settled inside the leaf.
This leaf was folded by an aphid.
