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By far, nitrogen (N) is the most widely applied nutrient for plant growth. It should come as no surprise, that symptoms of nitrogen deficiency readily develop with tobacco plants.
Tobacco that is deficient in magnesium (Mg) will initially develop symptoms on the lower or older foliage. These symptoms occur as an interveinal chlorosis that begins on the leaf margin, typically toward the leaf tip. Mg is mobile within plant tissues and will readily translocated from older leaves to the young developing tissues during limited Mg conditions.
Sulfur (S) deficiency can easily be mistaken for nitrogen (N) deficiency in tobacco. The ability to distinguish between the two is very important to determining a corrective measure.
Boron toxicity symptoms are described and management options discussed.
Calcium (Ca) is essential for proper plant development and leaf expansion. A calcium deficiency will first manifest in the youngest foliage because Ca is an immobile element within the plant. As calcium deficiency progresses, the developmental damages will also advance. The integral role of Ca in leaf development makes its early diagnosis vital to tobacco production.
Phosphorus deficiency of strawberries is discussed.
Interest in growing herbs for the retail and wholesale market has increased greatly over the past few years. Growers who have had success in the production of bedding plants have found another profitable avenue in herb production. Herbs have cultural requirements similar to bedding plants and it should be easy for greenhouse growers to add herbs to their production schedule. The majority of herbs discussed in this article can be sown, transplanted, and finished by the grower. This publication will focus on the production of the “top twelve” herbs and provides general guidelines for seed propagation.
This publication explains plant growth regulators for a variety of crops.
Providing a proper nutritional program is essential for growing top quality plants. Sampling the root substrate for pH and electrical conductivity (EC) with the PourThru extraction method is a quick and simple check of the nutritional status of a crop. The PourThru extraction method allows rapid on-site determination of pH and EC values. The values provide clues about a crop’s performance before deficiency or toxicity symptoms appear.
Zinc (Zn) deficiency has not been reported under field conditions. Most of the time, the soil will have enough micros to supplement any gaps in the chosen fertilizer plan. To present a more robust set of data, we induced zinc deficiency under controlled greenhouse studies for accurate diagnosis if the problem should arise. In NC State University trials, ornamental tobacco developed a silver cast to the leaves as the initial symptom of zinc deficiency.
Potassium (K) is one of the three core macronutrients, and consequently, deficiency symptoms manifest relatively quickly in tobacco. Potassium is a mobile element, which means it will translocate from mature tissues to the younger tissues where it is needed. This movement of K from older to younger foliage is what causes deficiency symptoms to develop first on the lower foliage.
Proper nutrition is essential for growing top quality geraniums. Sampling the root substrate for pH and electrical conductivity (EC) with the PourThru extraction method is a quick and simple check of the nutritional status of the crop and can provide immediate clues about a crop’s performance before deficiency or toxicity symptoms appear.
Diagnosis of nitrogen deficiency symptoms and corrective procedures discussed.
Molybdenum (Mo) deficiency has not been reported under field conditions. (Descriptions based on the book, Hunger Signs of Crops, 3rd Edition, edited by H.B. Sprague.) Under controlled greenhouse conditions, tobacco plants are slightly stunted when Mo is limited. The lower foliage of the plant develops a chlorosis, initially as a pale green, then the spots progress to a necrosis. The leaves may be crinkled and become bent or twisted.
Manganese (Mn) deficiency begins as an interveinal chlorosis on the upper leaves. As the symptoms progress, the interveinal chlorosis takes on a white netting type appearance. With advanced symptoms, small white spots develop and over time the spots enlarge into larger white spots.
Tobacco plants that are B deficient are stunted very early on in production when compared to healthy plants. Initial symptoms involve a noticeable distortion at the growing point. The youngest leaves will develop kinks and other unusual growth patterns. Additionally, the upper leaves will be very thick and brittle to the touch. It has a very distinct “ridged” feeling compared to healthy plants. Symptoms can progress very quickly once initial symptoms are observed. The distorted terminal bud will quickly become necrotic and may abscise from the plant. The older foliage will often become darker green in coloration and will also become distorted. The leaves will begin to curl downward and will take on a crinkled appearance.
Iron (Fe) deficiency does not readily occur under field conditions. To better catalog this deficiency, we induced Fe stress under a controlled greenhouse study. In NC State University trials, interveinal chlorosis (yellowing) developed on the youngest leaves. Over time the chlorotic areas became more pronounced.
Boron (B) is an essential element that frequently exhibits deficiency symptoms if it is in limited supply. Growers often apply additional B to avoid deficiencies, but if too much B is applied, there is the risk of B toxicity symptoms developing. Boron toxicities initially appear on the lower, older leaves. Early symptoms of boron toxicity will appear as wrinkling of the lower leaves and interveinal chlorosis along the leaf margin. The wrinkling is most likely caused by the lack of cell expansion when toxic levels of B are present. This wrinkling will develop across the leaf’s surface resulting in leaf deformation. Over time the interveinal chlorosis will move inward and develop over most of the leaf. Cells will rapidly die when excess B is supplied, resulting in necrotic spotting. With advanced symptomology, chlorosis and necrosis will progress up the plant to other leaves.
Phosphorus (P) deficiency in tobacco begins as a noticeable stunting when compared to a plant with a sufficient supply of P. Additionally, a P deficient tobacco plant may develop a darker green coloration of the upper foliage. Lower leaves will become chlorotic with a mottling of olive green leaf spots. The initial symptoms appearing on the lower foliage may be attributed to the fact that P is mobile within plant tissues and is translocated from these older leaves to the young developing tissues under periods of low P.
Ornamental sweetpotatoes are extremely heat-tolerant, tropical, perennial vines grown as annuals in North Carolina. They look great covering annual beds, hanging over walls or trailing from containers. This publication covers cultivars, how to select the plants, care through the growing season and pests and diseases.
Ethylene is an odorless, colorless gas which acts as a plant hormone. Thus it can be a growth regulator or a harmful pollutant of horticultural crops. Major losses caused by the “death hormone” can occur with high value crops such as greenhouse-grown potted plants and cut flowers, and fresh fruit and vegetables. Economic losses to greenhouse growers from ethylene pollution are reported each year and many more probably occur, but are not correctly diagnosed. This leaflet discusses ethylene sources and symptoms of damage, and how to prevent them
The poinsettia is a staple in greenhouse floriculture production. As the top selling potted flowering crop, successful poinsettia production is a must. Proper fertility is essential for quality plants. Monitoring and managing the root substrate pH and electrical conductivity (EC) is critical for proper poinsettia nutrition.
Copper (Cu) deficiency is extremely rare, consequently it is not normally seen in field conditions. To help with the diagnosis and treatment of Cu deficiency, we induced Cu stress under controlled greenhouse studies. In NC State University trials, symptoms first developed in the middle part of the plant. The middle region of the leaf developed brown veins, which quickly turned black. The tissue surrounding the veins became chlorotic. Symptoms progress up the plant to the younger leaves.
In this Brassica carinata (Ethiopian mustard) update, we highlight the symptoms of nitrogen deficiency. These images are part of a project by the Southeast Partnership for Advanced Renewables from Carinata (SPARC) to develop a diagnostic series for the identification of nutrient disorders of Carinata. Carinata is an exciting new crop used for a wide variety of primary and secondary agricultural products including cover crops, feed stock, high protein meal, and rocket jet fuel. It is similar in management to Canola given both Canola and Carinata are winter annual Brassica oilseed crops.
Proper nutrition is essential for producing quality pansies. Pansies make a large contribution to the net profit of many greenhouse operations and should be included in a nutritional monitoring program. Sampling the root substrate pH and electrical conductivity (EC) with the PourThru extraction method is a quick and simple check of the crop’s nutritional status.
The North Carolina State University (NCSU) Plant Disease and Insect Clinic offers a service for testing ethylene. This leaflet describes the sampling procedures to follow and fees for submitting ethylene pollution samples. (For more details about ethylene pollution in the greenhouse, consult HIL #530, entitled Ethylene: Sources, Symptoms, and Prevention for Greenhouse Crops .) This service is designed to test ethylene levels in greenhouses and is available to any greenhouse grower.