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Horticulture harvests are an important part of our diet that presently emerged as growth engine of the Indian as well as global economy. In India horticulture sector pays 38 per cent of the agricultural GDP and supports nearly 20 per cent of the agricultural work force with less than 14 per cent of the total cropped area. Horticulture crops such as vegetables, fruits, flowers, spices, condiments and plantation crops are an integral part of food, nutritional, and economic securities in India.

Physiological plant disorder is caused by non-pathological conditions such as poor light, weather damage, waterlogging or lack of nutrients affect the operation of the system caused. Physiological condition selected from diseases caused by plant pathogens such as viruses or fungi to distinguish. Although the physiological disorder symptoms may occur such as disease, they can often be prevented by changes in environmental conditions. However, once the nutritional deficiencies of plants showing symptoms, is likely to return that season yield will be reduced.

Apart from insects, pests and diseases, physiological disorders are one of the major threats to fruit industry which cause financial losses global. Over-all, the problems rise due to unfavorable environmental conditions and improper cultural practices which affect the normal plant growth and development is called as physiological disorders of plant. Ladaniya (2008) stated that the physiological disorder is that it is a function of physiological processes fruit tissue abnormality or failure due to abiotic stress, such as temperature, relative humidity, water stress, chemicals/ nutritional excess and deficiency.

Blossom end rot is a very common problem on green and ripe tomatoes. It started with light tan, water-soaked lesion, and then increased to black and tough. Although blossom blight itself caused only local damage, secondary biological invasions frequently lesions caused fruit rot complete.

Browning is due to boron deficiency caused. In general, boron deficiency symptoms in the formation of the curd, the plant externally visible. In the early stages, immersion in water and curd in the stem region of the surface occurs. As plant growth, into the hollow, soaked in water covers the cavity inner wall tissue. In the absence of progressive steps, areas of brown or pink color are visible, and hence, it is also called brown or reddish-brown or dark brown rot affected by the bitter taste. D

In general, germination of onion seeds is poor, and, in the case of old seed stocks, this problem is severe. Seeds soon lost viability in the ordinary storage state. However, cold storage conditions significantly increase the viability of seeds.

There is secondary elongating growth in the roots that gives a form of fork like structure to the root. This occurs in heavy soil due to soil compactness. An elongated radish root is encouraged by un-decomposed organic manure. It can be fixed by decreasing field moisture, balanced irrigation and also by sowing radish and carrot in sandy loam or light soil with loose and friable soil in nature.

Tip-burn is the marginal collapse and necrosis of rapidly spreading inner lettuce leaves, at or near the leaf margins. Typically, the condition occurs near harvest, when it may lead to complete crop failure. Early signs include discoloration of the veins and/or the growth of dark brown to black spots near or at the margins of the leaves. The necrotic areas coalesce as the disease progresses, creating a lesion up to several centimeters long.

In several cucurbits as well as other crops, BER is a physiological condition found (for example, tomato, brinjal and pepper). It typically occurs as a general rot at the flowering end of rising fruit. Usually, the blossom end rot is the result of inadequate or uneven irrigation, high humidity, or other variables that slow the flow of water through the plant. Slow water movement may also result in temporary calcium deficiencies leading to blossom end rot as calcium is added into the plant with the transpiration stream.

When the soil temperature stays at or below 20 0 C, seeds germinate poorly. During early spring-summer planting, this issue of seed germination occurs when seeds are to be sown at low temperature conditions.

This is one of the most serious difficulties in mango farming since it makes mango agriculture less rewarding for farmers. In one year (a year) and very little or no harvest next year, mango trees appear to bear huge crops (off year). This bieniality is therefore also present in normal ranges (Singh, 1990). 

Problems are low fruiting / non fruiting / irregular fruiting in the country’s litchi farming area. The potential of bear litchi has been identified as variety, although some of the bearing terminals in the present year will be more active in the next year (70-95 percent).

In the flesh of the fruit, tiny, 2-10 mm (depending on the cultivar) brown blemishes form. Below the surface, the tissue gets black and corky. At harvest or after cold storage, the skin develops depressed patches on the surface. These tend to develop as water-soaked patches on the skin around the calyx. Overall, these patches became darker and sunken than the skin around and developed entirely after one to two months in storage.

In grape growing areas in many parts of the world this illness is a very popular disorder. In this disorder, a bold beer is surrounded by shoot berries, and the name of the hen and of the chicken disorder is like a hen, as bold berry and chicken. The fruit has a sour taste. The signs are the death of rising tips, falling leaves and the fragility of new shoots. With the development of interveinal chlorosis between the edges, the leaves may be deformed, and this is particularly evident after fruiting.

It’s because it impacts the active development of the plant at a low temperature. Yellowing of the leaves and severe destruction of the tissue. In cases of flowering plants, the stalk carrying the bunches freely lengthens and drapes down the complete inflorescence.

This is primarily a physiological condition and, after heavy rains or heavy irrigation during hot weather, is mostly due to high atmospheric humidity. Two forms of splitting have been found, namely radial and transverse. There is more frequent radial cracking than transverse cracking. While splitting down to the inner core is very unusual, partial splitting is more prevalent.

Bronzing is a complex nutritional condition in guava (Psidium guajava L.). It manifests in the interveinal tissue of older leaves as bronze or copper colour development, while terminal leaves remain green. This is attributable to the inadequacy of elements P, K and Zn. Bad management and low soil fertility coupled with soil acidity are often due to it.

Twitching is a condition occurring predominantly on the surface of the fruit which is exposed to direct sunlight; however, it is not well understood what the source of the disease is. Growth in immature fruits cannot be detected during later stages of fruit maturity. On cv. Golden Solo Party there are a few examples. This is termed the “frog skin” or “fox skin.” It shows on the fruit’s surface as the Dark Brown Flecks. 

Internal necrosis has been observed in Aonla (Emblica officinalis Gaertn.) fruits. Francis cultivar, preceded by Banarsi, is highly susceptible. The symptoms begin with browning of the inner majority of the mesocarpic tissue in the 2nd or 3rd week of September at the time of endocarp hardening, which later spreads to the epicarp, resulting in brownish black flesh appearance. Internal fruit necrosis is associated with boron deficiency during the fruit development.

Fruit cracking is an important physiological disorder found in some commercial cultivars of Bael (Aegle marmelos), which occurs just before the ripening stage. It is correlated with abrupt changes, such as temperature and humidity, in weather conditions. Heavy irrigation or precipitation is also one of the causes of this disease after prolonged drought.

Fruit cracking is a serious problem of pomegranate (Punica granatum L.) particularly in arid climate. Cracked fruits are sweet but unfit for long distance transportation. Incidence of cracked fruits varies from 10 to 70 % depending upon the prevailing environmental conditions. Longitudinal or radial splitting of rind surface occurs.

Ordinarily, fruit bears a single crown, but fruit bears more than one in some cases. The top of the fruit will therefore be smooth and wide and the fruit will not be ideal for canning. These fruits have an insipid taste and are corky. It is intended to be an inherited character, often found in the Cayenne group to which the Kew variety belongs.

The normal blooming stem on the greenhouse rose has fully developed sepals, petals and reproductive organs. The inability to build a bloom at the apical end of the stem is a typical phenomenon which in such shoots is termed blind. There are sepals and petals; however, they are not complete or aborted in the reproductive portions.

Leaves in the centres appear bleached and may have brown edges. Shade should be provided to reduce the light level to 1800-2500-foot candles to control this problem.

Gladiolus is a fluoride pollution indicator plant, as it expresses the effects of fluorine at very low levels. Symptoms of scorching of the leaves look like drying of the tips of the leaves. A strong application of super phosphate is also associated with fluoride toxicity. By spraying 5 percent lime or Magnesium sulphate, it decreases

The calyx may be either half or entirely broken. The petals are stripped of their support, which contributes to the petals being bent down. The continuity of the form and arrangement of the flower is thus lost. Splitting, particularly where light and temperature fluctuate is correlated with weather. By maintaining the night temperature at 5 ° F, some reduction in splitting can be achieved. More calyx splits were caused by high plant density per unit area. 

An anomaly characterized by numerous leaves, short petioles and small laminae that offer a bushy appearance known as bushiness to some gerbera cultivars. The nodes are not clearly differentiated and no elongation of the internode is seen.

Smaller leaves are produced and finally a rosette is formed. Internodal length reduction and apex-tapering of the stem. Most of the nuts are tiny and deformed, assuming they are produced. Drainage is poor and soil and pan/hard clay pan fertility are low.

Little leaf of cashew (Anacardium occidentale L.) is caused due to the deficiency of zinc. The leaves remain small in size giving rosette appearance.

The presence of nuts in the kernel is known as stubborn nuts or seedless or imperfect nuts and is frequent in coconut (Cocos nucifera L.). The nozzles impacted are oblong compared with the typical circular form of the nozzles and less than normal husk is generated. The often-breaking shell over the course of the development is the most typical feature of the barren nut. 

Black nose is used for the unusually shrinking and darker date end. The most susceptible cultivars for this physiological state are Deglet Nour and Hayani. The black nose result is an over exam of the epidermis, in particular many little cross-sectional exams or ruptures near the end of the style of the foetus. There is a substantial shrinkage and darkening in proportion to the quantity of the controls and moist conditions on Khalaal level are related to them.

Symptoms of pale or yellow-green leaves (chlorosis) first occur in the older leaves. At the leaf margins reaching toward the midrib or central vein, reddish tints gradually emerge. The leaves are thin. Growth overall is markedly reduced. Deficiency results in rhizome yield loss.

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