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Pyrethrum is the most widely used botanical insecticide. The active ingredient, pyrethrin, is extracted from a chrysanthemum plant, grown primarily in Kenya, Rwanda, Tanzania and Ecuador. Pyrethrum is the powdered, dried flower head of the pyrethrum daisy, Chrysanthemum cinerariaefolium.

Medicines used for controlling insect pests are known as Pesicides which have assumed great importance in today’s high yielding and intensive agricultural system as well as public health programme, all over the world. The term pesticide is an all-inclusive word meaning killer of pests and includes substances used for controlling, preventing, destroying, repelling or mitigating any pest.

Sixteen chemical elements are known to be important for a plant growth, their metabolic activities and survival. These can be divided in to two main groups

Fruit drop just before harvest is a serious problem for various crop varieties. The severity of fruit drop is influenced by several factors but plant stress and premature ethylene production is at the basis of true physiological drop. Stress factors such as late season heat, primary and secondary pest infestation, and nutrient imbalance or deficiency, and heavy summer pruning, all can contribute to drop.

The use of flower inducers stimulates flower growth during the resting year so the tree produces annually. Flower inducers can also increase the number of viable blooms during the natural fruit producing year, for an increase in production. These can also be used on varieties that provide a crop every year, to boost harvest.

Anti-transpirants are usually foliar sprays, although they may sometimes be used more conveniently as dips for immersing the above ground plant parts. Foliar sprays may reduce transpiration in three different ways

Plant growth regulators or phytohormones are organic substances produced naturally in higher plants, controlling growth or other physiological functions at a site remote from its place of production and active in minute amounts. Thimmann in1948 proposed the term Phytohormone as these hormones are synthesized in plants (Thimmann, 1963).

Proper selection of plant health medicines like fungicide, bactericide, antibiotics, algaecide, viricide, nematicide, weedicide, plant harmones and auxins and its application at the correct dose and the proper time are highly essential for the management of plant health. The basic requirement of an application method is that it delivers the chemical to the site where the active compound will prevent the pathogen/pest damaging the plant. 

Seed is a basic input to raise the crop plants. Healthy seeds produces the healthy crop. However, the seed carries different pathogens either externally or sometimes internally in the seed to affect the seed emergence and healthy seedling growth. Therefore, the seed treatment with fungicides/bactericides, based on the infection of the pathogen, is highly essential to counter the attack and infection of these pathogens to the germinating seedlings.

Protozoan parasites are Trypanosomatids of the class Kinetoplastida predominately restricted to invertebrate hosts (i.e. possess a monoxenous lifecycle). However, several genera are pathogenic to humans, animals and plants, and have an invertebrate vector that facilitates their transmission (i.e. possess a dixenous life-cycle).

The algae associated with the plants belongs to the Order Trentepohliales (Ulvophyceae, Chlorophyta). These are filamentous green algae parasitic to higher plants, generally causing minor diseases characterized by negligible leaf spots, but on certain crops, in moist environments, these algal diseases can cause economic injury to plant leaves, fruits, and stems (Nelson, 2008).

Nematodes are multicellular, unsegmented, bilaterally symmetrical roundworms belonging to pseudocoelomates class of creatures. Many of them are parasites of plants. Different crops species are susceptible to several species of plant parasitic nematodes which limits the yield and quality of the food harvest. Root-knot nematodes (Meloidogyne spp.), foliar nematodes (Aphelenchoides spp.), root-lesion nematodes (Pratylenchus spp.) reniform nematodes (Rotylenchulus spp.) and other ectoparasitic nematodes are the important nematodes species to infect the crop plants.

Plant viruses cause severe crop losses worldwide. Conventional control strategies, such as cultural methods and biocide applications have limited success at mitigating the impact of plant viruses.

It is used in the control of bacterial leaf spots, blights, and cankers mostly on fruits crops and ornamentals. The Bordeaux mixture, however, can cause burning of leaves or russeting of fruit such as apples when applied in cool, wet weather. The phytotoxicity of Bordeaux is reduced by increasing the ratio of hydrated lime to copper sulfate. Copper is the only ingredient in the Bordeaux mixture that is toxic to pathogens and, sometimes, to plants, whereas the role of lime is primarily that of a “safener.”

A same active ingredient are available in the market with different trade name and are the product of different companies. These may also differ in their formulation and hazard class (table 7), the knowledge of which is necessary in the plant disease management in view of their effect on the pathogen, ecosystem and environment.

Development of fungicide resistance in a fungal disease pathogen is a major concern for some of the important diseases in their management. This can be overcome by designing of fungicide use strategies to manage the threat of fungicide resistance.

There are several fungicidal molecules available in the market, some of which are specific for certain diseases/pathogens while others are broad spectrum and can be used against a range of diseases. However, for proper control measures a knowledge of disease specific fungicide are very important. Ready-Reckoner for disease specific fungicide (Table 4) makes available the option for selection of alternative fungicide in the management of specific disease.

Actino-IronOG (Streptomyces lydicus WYEC)

Biological soil and seed treatment for Fusarium, Rhizoctonia, Pythium, and Phytophthora with added iron.

Fungicide which is effective only if applied prior to fungal infection is called a protectant, eg. Zineb, Sulphur. Protectant fungicides are prophylactic in their behaviour.

Fungi are one of the major causes of crop damage which affect crop yield, quality and revenue. Therefore to control these fungal diseases, fungicidal crop protection products are used at different stages of crop growth. Many of our current fungicides produce excellent results with respect to efficacy, crop quality, food safety, and improved cost/profit ratios of agricultural production.

Plant diseases are caused by different etiological agents like Fungi, Bacteria, Viruses, Viroids, Phytoplasmas, Rickettsia like bacteria, Nematodes, Algae and Protozoan parasites. To control these specific pathogens and the diseases caused by them, a specific group of medicine/chemical molecule is required.

All varieties of rose are susceptible to this disease. It is an important disease of rose which causes a sharp reduction in number and size of fl owers.

The disease appears as tumour like swelling or galls on leaf veins, leaf stalks, peduncles, stems and on fruits. The galls on the vein give a swollen and hanging appearance to the leaves. These are elongated, looks glossy in beginning but later rupture to become rough and corky. When stems remain succulent, numerous tumours may form on them. In severe case, the plant may kill prematurely.

The symptom appears as numerous, circular, light yellow to dark yellow spots on both the surfaces of leaves but is more prominent on the upper surface. The spot may coalesce to form large, irregular patches and soon entire leaf turns yellow and dries. Affected leaves appear as reddish-brown in colour. Excessive spotting destroys green tissues and becomes weak and yield reduced drastically

It is known by different names such as Ramularia leaf spot, rust, bird’s eye spot, grey spots, and white spot. It mostly attacks leaves but can also attack fruit stalks and also fruits.

The fi rst symptom of disease appears in early spring soon after leaves come out of buds. Affected leaves become distorted and fold over as tips directed backwards. The whole lamina puckered except tip and blistered. In some leaves, part of leaf show distortion. Blistered portions are thicker, softer than the normal leaf blade. The affected areas remain green for a while and gradually become yellow and fi nally turn reddish-purple in colour. 

It is a serious disease of apple which not only reduces the quality and size of fruit but also cause premature fruit drop and defoliation. Fruit loses its marketability due to poor quality. It also reduces storage time and cause loss up to 70%.

The disease attacks all the growth stages of plant affecting all above-ground parts. Plant covered with powdery patches leads to distortion, malformation and discolouration of leaves especially young leaves. Powdery patches gradually turn to grey and fi nally dark colour. Affected fl ower fails to develop fruit. Young berries turn black, irregular in shape and develop cracks. Sometimes berries ripe partially and rot. Vines get wilted.

Citrus crop includes lime, lemon, sweet orange, mandarin orange, Kamala orange, grapefruit, malta and pomelo etc. The disease which attacks one species of citrus mostly attacks other species also.

It is a very common disease of mango. It is otherwise known as blossom blight, leaf spot, twig blight or wither tip.

It is a very important and commonly found disease of chili which observed in field as well as in storage. It is also known as anthracnose disease which is mostly seen in tropical and sub tropical regions.

It is a very common disease found in all the onion and garlic growing areas. It mostly attacks the bulb as well as the seed crop. The infection or severity of the disease is more in Kharif crop causing 60% yield loss.

Disease appears later part of the crop season mostly during blossoming period. The first sign of the disease is the appearance of small brown patches on the leaves mostly on basal leaves which starts from tip or margin of leaves and spread downwards or inward directions.

The disease is seen at 3-4 leaves stage. Scattered, irregular, yellowish patches appear on the upper surface of the leaves and stipules. On the corresponding under surface of these patches, a greyish violet fi ne cottony mildew growth is seen. Infected tissue soon dies and turns brown. The disease fi rst appears on lower leaves and later spreads to upper leaves.

The disease i s seen at all crop growing stages. The fi rst symptoms appear at the time of emergence of seedlings, when the cotyledons are attacked. They become yellow and turn brown followed by wilting and drying of the affected seedlings. In the fi eld, the wilting symptoms appear in patches. First of all, the older leaves become yellow, loose their turgidity, wilt, turn brown and droop.

Wilt appears in the fi eld as patches is both seedling stage and developed plants. Symptoms include drooping and wilting of uppermost leaves. Plants become completely yellow and die. Plants are affected during the pod fi lling stages, seeds are often shrivelled. There will be rotting at the basal portion of the plant. Discoloration of vascular bundle are noticed when the stem is spitted
open.

All the above ground parts of the plant are affected. There is development of round and elongated spots surrounded by brownish red margin on the leafl ets. At later stage spots coalesce and entire leaf turns brown. On green pods, the lesions are usually circular with dark margin and pin head like dark dots representing the pycnidia in concentric circles.

The initial symptom of Alternaria brassiciola appears as small, dark colored spots which enlarge rapidly to form circular lesions. Under humid conditions a bluish velvety fungal growth is seen in the centre of these spots. Spots caused by Alternaria brassicae are almost similar to those produce by Alternaria brassicicola but are comparatively smaller and lighter in colour. When many spots are formed on the leaves, the leaves turn yellow and dry prematurely. Formation of pods and seeds are adversely affected.

The plants wilt at the time of grain fi lling stage. A light brown water soaked area is seen at the stem base. Sclerotia can be seen on the outer region of stalk when the plants get older. White mycelial growth with large sclerotial bodies is seen over the stem pith. The stem often breaks down at the point of infection.

The disease was fi rst reported in Java in 1893 and is prevalent in all sugarcane growing countries. In India the disease occurs in an epiphytotic form in Uttar Pradesh and Bihar during 1939-1940 and 1946-1947 and cause severe damage that threatened the existence of sugar industries.

Loose smut of wheat occurs worldwide but is more abundant and serious in humid and sub – humid regions. In India, this disease is found in all wheat growing areas but the incidence is generally more in comparatively cooler and moist parts of north India than south India. The yield loss may go up to 30% due to this disease.

Coconut is a tall un-branched palm growing to a height of 15-30 m. it has a stout trunkraising from the swollen base which is known as bole. It is surrounded by a mass of fibrous. The stem is terminating into a radiating crown of leaves. Leaves are known as fronds. Palm is monoecious produces one inflorescence is enclosed in a strong tough double sheath called as spathe. Fruit is known as drupe, large in size, one seeded, round, ovoid I shape and the fruit has smooth thin green skin known as exocarp below which there is a thick fibrous hook known as mesocarp. Tall varieties live up to 80 . 100 years and dwarf varieties are live up to 40 . 60 years. Tall varieties begin flowering 5-7 years after planting and dwarf varieties . 3 years after planting

1. The botanical fruit type of coconut is
   1. Drupe
   2. Hesperidium
   3. Berry
   4. Capsule
2. Palm inflorescence are ____
   1. Monoecious
   2. Male
   3. Dioecious
   4. Female

1. The leaf roller is an important pest of
   1. Lemongrass
   2. Citronella
   3. Mint
   4. Bursera
2. The following aromatic plants is susceptible to powdery mildew
   1. Sacred basil
   2. Thyme
   3. Geranium
   4. Rosemary
3. Meloidogyne hapla is reported to affect
   1. Thyme
   2. Geranium
   3. Sage
   4. Lavender

1. The economic part of bursera is
   1. Root
   2. Leaves
   3. Stem and root
   4. Berries
2. Oil yield of thyme is
   1. 62 kg /ha
   2. 21 kg /ha
   3. 35 kg /ha
   4. 11 kg /ha
3. The oil yield of anise is
   1. 15 kg/ha
   2. 5 kg/ha
   3. 25 kg/ha
   4. 50 kg/ha

1. Pick odd one out
   1. Nima
   2. Pragati
   3. Jeva 2
   4. Praman
2. The following type of vetiver is high in oil yield but its oil quality is inferior
   1. East Indian Type
   2. North Indian Type
   3. West Indian Type
   4. South Indian Type
3. Vaishnavi is a variety of
   1. Vetiver
   2. Lemongrass
   3. Palmarosa
   4. Patchouli

1. Seed rate of celery is
   1. 0.5 kg/ha
   2. 2.5 kg/ha
   3. 0.25 kg/ha
   4. 1.5 kg/ha
2. Davana seedlings will be ready for transplanting
   1. 10 – 12 weeks after sowing
   2. 6 – 8 weeks after sowing
   3. 4 – 5 weeks after sowing
   4. 2 – 3 weeks after sowing
3. Bursera planting is done at a spacing of
   1. 2 m x 2 m
   2. 4 m x 4 m
   3. 6 m x 6 m
   4. 8 m x 8 m

1. The botanical name of West Indian birch is
   1. Bursera simaruba
   2. Bursera serratea
   3. Bursera gumifera
   4. Bursera javanica
2. The following genus is commonly known as khus
   1. Cymbopogan
   2. Chrysopogan
   3. Ocimum
   4. Apium
3. Ceylon citronella indigenous to
   1. India
   2. China
   3. Central Africa
   4. Ceylon

1. The major disease of isabgol is
   1. Powdery mildew
   2. Leaf spot
   3. leaf blight
   4. Downey mildew
2. The damping off is a series disease in
   1. Ipecac
   2. Aloe
   3. Indian penny wart
   4. Glory lilly
3. The following medicinal plants is affected by termites causes a lot of damage to young plants
   1. Gymnema
   2. Glory lilly
   3. Henbane
   4. Liquorice

1. The average dry yield of gymnema is
   1. 2 – 3 kg/plant
   2. 5 – 6 kg/plant
   3. 20 – 25 kg/plant
   4. 10 – 12 kg/plant
2. Isabgol will be ready for harvest in
   1. 80 – 90 days
   2. 60 – 70days
   3. 140 – 150 days
   4. 110 – 130 days
3. The liquorice uprooting in the month of
   1. November – December
   2. February – March
   3. August – September
   4. June – July