Cucumber - Science topic

For tomatoes the pollen is sensitive to high temperatures. In summer many tomatoes become male sterile.

I would suggest your ability to make crosses would be improved in greenhouse chambers where lighting and temperature are controlled.

Pollen can be affected by nutrition and complete plant analysis can be combined with drip line and foliar application to optimize the nutrition compared literature values.

Dear Aryeeson Gerrard

Please, read this, it is in Spanish:

And this one:

I hope this helps you.

As Prof. Ignatov said; it's too hard and complicated identification of plant viruses by symptoms

But in my opinion, the best image collection for cucurbits diseases and their control is this Book:

Compendium of Cucurbit Diseases and Pests, Second Edition

ISBN:978-0-89054-574-4

Medhat Elsahookie, thank you very much for your valuable support and interesting information.

With regards

Visit also the following useful link: https://ejfs.journals.ekb.eg/article_48484_ab57cfd6129c269a96d2a0bb33377fba.pdf

Imidachloprid

We have isolated Fusarium oxysporum from clinical and environmental materials on sevearl media, such as potato dextrose agar, Sabouraud dextrose agar and oat meal agar.

We have published two papers on oculomycosis in animals due to Fusarium solani and both papers can be easily downloaded from the Research Gate.

Hi Rizwan,

Generally, medicinal plants do contain active chemicals which are sensitive to heat. Therefore low drying temperatures between 30 and 50°C are recommended to protect sensitive active ingredients.

Depending on major phytochemicals available in the plant material which are needed for further analysis, you can decide the drying temperature. Also considering the duration of heat application, pressure in the drying chamber, the method used in drying herbal material etc. you have to decide it.

For further details, you could refer ;

https://library.wur.nl/frontis/medicinal_aromatic_plants/17_muller.pdf

Thanks.

I haven't faced this issue but

Try it, your problem will solve

Very good question . Though the question is outside my field . I am tempted to raise this question . What is your opinion , these days, many times , any alteration in original gene sequence or genome , application of biotechnological tools like gene editing through CRISPR or RNAi application are often criticised for genetically modified genome as end product , regardless of crop . Is it debatable or an accepted strategy, since many countries still have some stigma with genetically modified crops....

Please see the RG link below.

This is a nutrient diffiency symptom

Glycyrrhizin obtained from roots of liquorice (Glycyrrhiza glabra) may be useful for treatment of COVID-19.

Healthy eating and proper exercise are good ways to keep fit during normal times. However, during the epidemic, maintain personal hygiene, wash hands frequently, pay attention to disinfection, and wear masks to protect ourselves will be more effective.

There are many fungi that affect cucurbit plants, including many, and they are similar in their symptoms of external infection as Botrytis , Colletotrichum orbiculare and Fusarium oxysporum or downy mildew diseases. Therefore, it is better to grow fungi on a PDA medium or direct slides and the microscopic photo is best for diagnosis.

Thanks a lot Dr. Robert and Dr. Fatima for your valuable answers

Alex , this looks like typical iron deficiency...

Hello, see info attached may be useful for you.

Dear Shahram

From my point of view, P and micrinutrients are essential but you should be sure about other factors such as soil moisture.

Regards

Weria

I have never worked with cucumber. Searching and found this :

Cucumber had most sensitivity to root- knot nematodes infection especially meloidgyne incognita I had that work before

It looks like angular leaf spot to me, see the link below.

https://www.seminis-us.com/resources/agronomic-spotlights/important-cucumber-diseases/

I have not contacted yet people of this company. You are right, if it really works why not publish their results (with appropriate controls) to make it public and not just an article written by journalists?? This science is called (in french) génodique. Have a look at Sternheimer J. musique des particules éémentaires Comptes rendus de l'Académie des Sciences Paris II, 297: 829, 1983. and Henty M. Ondes d'échelles (on line) 2016. and also RG

Frank, thank you! I have found this report and some others about P. aptato on cucurbits in field, but not about greenhouse cucumber. Some colleagues said that strains from squash were not virulent for cucumbers.

Alex

We can calculate degree parthenocarpy of cucumber (cucumis serious L) whith calculate number of cucumber flowers.

Pay attention to air humidity, It may cause a lot of deceases. Day/night temperatures is very important for fruit set.

@ Elaheh Gerami

Please have a look at the following links.

Thanks!

This paper discussed about partenocarpy in cucumber

As Jonath Alumona has aptly remarked the double cropping of cucumber will be considered a monoculture and as monocultures favor adaptation of pests and disease are double crop rotation might be more useful. The use of cabbage or broccoli established as the autumn crop and using as a follow the cucumber provides rotation. To keep a summer crop the use of sweet potato may be tried as a triple cropping system. White plastic mulch might be best for the summer and autumn crops and black mulch for the spring cucumbers. Spring cucumbers can be a short duration variety, as well as summer sweet potato, and fall cabbage and broccoli might also be focused on short duration crop sequences. The cucumber is cucurbit, the sweet potato a convulacae, and cabbage or broccoli a brassica. This more extended rotation will help prevent the adaptation of pest and diseases as well as composting all wastes with manures and high temperature to provide nutrition and eliminate disease and pests.

Great, if your calculation is under a different air pressure, then it makes sense.

As for the Kc and Ko, actually to me, the difference is not "so large". An accurate number would be difficult due to several reasons.

1) most Kc and Ko come from in vitro measurement, and it's quite different environment in vivo.

2) As you mentioned, small difference in the structure of Rubisco. Mutation on several loci already can change the affinity significantly. So it is reasonable to vary by tens of ppm for Kc.

Anyway, we still can obtain an "accurate" Farquhar model even though the Kc and Ko are biased. The deviation caused by Kc and Ko can be mostly compensated by Vmax and gm. To me, those biased numbers would still be useful for a comparison study done by the same protocol and same person :P

And another thing I'd like to mention is that I looked into the paper Moualeu‐Ngangue et al., (2017), in my opinion, I would say this method is not robust.

For example, in its attached excel worsheet, the best fitted results a SSE=4.233.

It's very easy to find other combinations of {Vcmax,J,Rd,Tau} which results a very close SSE. I listed two I found {Vcmax=163,J=150,Rd=0,Tau=0.55,SSE=4.515} and {Vcmax=120,J=121,Rd=0,Tau=0.44,SSE=4.952}. Of course, gm in the worksheet also varies a lot. Therefore this estimation is not stable. So be careful with the number you get from this method.

Best regards,

Yi

You've tried adding a drop of Tween-20? That works for hydrophobic spores, although it can be fungitoxic. There was a time when we sprayed spores in liquid Freon, but that might be illegal now. Depending on your spray rig, you might be able to use a 0.01-0.02 % water-agar solution, which holds spores more uniformly in suspension.

Hi my friend

To measure the area of a leaf

First weighs a paper at a specified size (5 cm * 5 cm = 25 cm²)

Then cut the paper to the size of the leaf and weigh the piece

The area of the leaf is based on the weight of the paper.

Jai Ghosh thanks for your answer Dr. Ghosh, it is very helpful.

Good information. Thank you...

No such tools are used for quality requirements ...but some methods are used..

The list of Mackauer and Stary (1967) is very outdated with more than 51 years old, incredible as someone recommends a bibliographical reference so old. The CABI 2018 list that I recommend is the most updated and the most complete containing all the parasitoid species so far reported parasitizing Aphis gossypi.

Mehdi Ali,

peppers, tomato, eggplant are not compartible with cucurbits in humidity/temperature balance , cucumber is more susceptible to the same pathogens that infect zucchini. you can test other cucurbits.

Alex

Procedure

Neutron probe method

Macroscopically, check the colouration and you can use 3M kits, fasting method as mentioned by Eshak.

Agreed with Bozena.

just wanted to ask is there any incidence of pests like aphids or jassids. Pests can also causing the leaf curling and spread of virus. But by the pics, the first explanation would be water stress.

You can grow any summer vagetable , provided you have dehumidifier installed in polyhouse....

Your welcome Dr. Kumar

Be successful

Thank You

Very interesting question indeed. Any organic residue of such high C:N ratio will not be able to benefit cucumber, especially in a pot experiment, but surely it will aid in improving the physical properties of the treated soil. Release of nutrients in from organic residues can be accelerated by adding some nitrogen to narrow down C:N ratio.Unless C: N ratio buffers around 20-30:1, direct implications of organic residues on changes in soil fertility will be difficult to be realised in such short duration crops.Residual effect of such residues will be increasingly felt. Soil properties and their baseline microbial diversity also play important role in release of nutrients through such crop residues...

I think it is a physiological reaction of the plant to the pH of the substrate.

Also, I think it is correlated with deficiency of potassium, light, temperature and atmospheric humidity. You have to check.

united Arab emirates

Thank you Garcia

You may firstly calculate the saturated concentration of dissolved methane (at standard state) out, via an equation of temperature and salinity. The later can be found in Table A2 of Wanninkhof (1992). And then you could work out the methane concentration via the saturated concentration and the saturation value.

Reference

Wanninkhof, R., 1992. Relationship between wind-speed and gas exchange over the ocean. J. Geophys. Res., 97, 7373–7382.

I know this is not powdery mildew infection and it is an extra infection I experienced in some replicates during the greenhouse trial. 

I do not follow your question. However, when I was working with cucumber and other cucurbit genetics, I put a paper bag over the young fruit. The fruits receiving this treatment came through, whereas some of the ones not covered either rotted because of insect holes, or diseases which seemed to be associated with soil contact.

Dear M. Alizadeh

To prepare the leaf discs around 30 ml of (1.5% agar solution was poured into a 7 cm Petri dish) after cooling the agar (simply agar)  leaf in this media and condition was able to survive 10 days, all tool used in cutting the leaves were sterilized in 90% ethanol to reduce contamination. I was able to keep the leaf for at least 10 days simply. I add parafilm covering over the dishes.

Hoping this will be helpful            

Regards

Prof. Houda Kawas

Dear Prof. Dr. Jawad, 

I agree with Assist. Prof. Ahmed.

You also can see the attached articles :

Best greeting

Some cucumber varieties grown under  green house conditions in US and some parts of Europe are parthenocarpic.  Middle East and some East Asian countries also cultivate seedless varieties. But majority are cultivated through seed. Apart from Cucumis sativus and C. melo flexuosus, Marah oregana is also a cucumber ; western wild cucumber. One can search the literature for this scientific name  and may get some inputs.

Hello Dear

Methyl salicylate, an ,has been shown to attract natural enemies and affect herbivore behavior. Best regards

Before starting such studies soil index such as fertility status, reaction etc. is needed to be estimated and accordingly nutritional studies are planned. So far as physiological index is concerned, on the basis of objectivity of your studies, plant growth and development parameters of plants in poly tunnel need to ascertained for recording data.

 I agree totally withnDr, Weston Testo's suggestions

Dr. Srinathrao 

This link is similar to you question

Hi  Pfano : The best way to preserve the fungi is to keep the most structure that can survive to long term, for the Sclerotinia sclerotiorum the best is to preserve the sclerotia, you can preserve it as dry in room temp for more than 1 year , but if you want to preserve for long term dry the sclerotia and keep it in vial at 4C or -80C.  Please find the attached file for the useful paper.

Mr. singh 

  you can spray Ag No3 (300 ppm) @ 3-4 leaf stage and 15 days after 1st spray he may get 10% of male flower in seedless cucumber, if its gynocecious line,or if its monoecious  line you can directly self it.

Please, take a look at this paper:

E. Gamalero, G. Berta, N. Massa, B.R. Glick and G. Lingua

Interactions between Pseudomonas putida UW4 and

Gigaspora rosea BEG9 and their consequences for the

growth of cucumber under salt-stress conditions

Journal of Applied Microbiology 108 (2010): 236-245

doi:10.1111/j.1365-2672.2009.04414.x

Thank you!

Dear Bhim,

As you stated, you want to do your experiment at polyhouse condition. Design of your project is changed according to the some factors; irrigation system, plantation from pot or land... If seeds of cucumber are planting directly from land is better to follow of RCB Design.

Kind regards,

Rabar,

Hi Arshad

I hope these publications will help you

1- "Effects of sowing date and pinching on broccoli seed production"

(A. A. El-Yazied et al., 2007)

for a copy please send a message to my friend hany gamal on his researchgate page

2- Effect of head decapitation and planting density on quality seed production

of sprouting broccoli (Brassica oleracea var. italica L.)

(Mehta et al., 2015)

download this link

If there is a need to analyze the sample for nutrients such as N or protein, the temperature should not exceed 65C. Dry until constant weight is achieved.

Both the defenses play an integral role in HPR and it all depends which is working in your case. Generally against sucking pests, its the induced response which is more pronounced.

Dear  Remi Cornwall

Thanks a million

Hi,

I can not see the root system clearly in the picture but seems to me healthy. This kind of symptoms can be seen with abiotic factors like phytotoxicity. Did you sprayed anything on plant? Otherwise you need to cut a little part of stem just below the yellow part longitudinally or cross and can see if there is any kind of discoloration. If yes there is chance of Fusarium infection. Very prevalent in cucumber. Also you need to collect more information such as, did you over-watered them, or any kind of spray, added fertilizer and also is there any discoloration/ injury in roots you found. Hope it will help.

Thank you Thom

Dear Abdalla Abdelrahim Satti, 

 Biocontrol works best when you rely on established procedures. The biocontrol agent producers have invested many years of research to offer these procedures. They give you very detailed informations concerning the necessary prey densities, the moments of release, the techniques of release (to avoid the activities of ants),  and the dosage of predators or parasitoids. They have developed wrappings that avoid cannibalism and they experimented the number of release points that conduct to satisfying and reliable results. Furthermore, they have developed in International Working Group 5-Year Projects all that quality control experiments and procedures to assure that the population you release is able to assume the job they are released for. Having all these data not only published in literature but assured by biofactories, I cannot understand, why people return to the beginnings and try to do it themselves again and again. It is not less expensive to invest all those hours to reinvent all of this, than to apply the products that are existing in the markets. Perhaps you can pass a technical semester in one of the biofactories IBMA represents worldwide, to discover all of these procedures. Wish you the best of luck,

Carola Meierrose 

Hi,

for more information please find thes articles and websites. Maybe its can help you.

What is your aim? why not tae out some of the seeds and go for a germination test?