UNIVERSIDAD DE GUANAJUATO.PRACTICAS 4.

SORGHUM CROP.

TEACHER HECTOR GORDON.

STUDENT JOSE MARINO ARAUJO MENDOZA.

• Sorghum (Sorghum bicolor L. moench) was probably initially domesticated in central Africa, in the region of Etiopia and Sudan.

• Subsecuently, cultivation of sorghum spread througout Africa and Asia and finally to the Americas and Australia.

• Today it is one of the world’s major food crops, particular in Areas of high temperature and low rain fall.

• Its used for human consumption and to feed different kinds of livestocks such as birds, pigs and cows.

Sorghum Taxonomy.• Kingdom-Plantae.• Subkingdom-Tracheobionta.• Superdivision-Spermatophyta.• Class-Liliopsida.• Subclass-Commelinidae.• Order-Cyperales.• Family-Poaceae (Grass).• Genus-Sorghum.• Species-Sorghum bicolor.• Subspecies-Sorghum bicolor ssp. Arundinaceum-common wild sorghum.• Subspecies- Sorghum bicolor ssp. Bicolor-grain sorghum.• Subspecies-Sorghum bicolor ssp. drummondii-sudan grass.• Species-Sorghum almum –columbus grass.• Species-Sorghum helepense-johnson grass.• Species-Sorghum propiquum-sorghum.

• Sorghum can reach a height from 1-2 metters, it has flowers in panicles, and seeds of 3 mm with a circular or egg form, wich it depends of the variety, with a color the one can be black, red or yellow.

• Its roots can growth 2 metters depending of the soil and water available to the crop.

• It has flowers with stamens and pistils, but in Sudan have been found dioicious varietys.

• Area estilar- stylar area.• Endosperma corneo- corneous endosperm.• Endosperma harinoso- flowry endosperm.• Escutelo- scutellum.• Embrión- embryo.• Epicarpio- epicarp.• Mesocarpio- mesocarp.

Sorghum.• 1. Day length: Day length neutral &

photosensitive types• 2. Rainfall: 600 –1,500mm• 3. Altitude: 900 –1,700m• 4. Temperature: 23 –32oC • 5. Soil Type: Light, well –drained loams• Sensitive to acidic soils• 6. Root systems: Extensive & Deep rooted • 7. Photosynthetic Activity : Efficient

As a crop for climate change adaptation

• 1.Moderate input requirements .• 2.Easy to grow• 3.Fast growth rate• 4.Highly responsive to Improved management• 5.Drought tolerance• 6.Widely adapted• 7.Easily extract nutrients from poor soils • 8.Fit well in many Tillage systems, crop

Diversification programs and cropping patterns

• Sorghum is the third grain most used in the world to feed human population, 75% of the world sorghums produccion is destinated for human consumption.

• In places like India, Africa and China , sorghum provides 70% of the calories of the human diet.

• Sorghum is used to make meals like binder sausages, flour, milkshakes, beer and also to produce alcohol an many more uses in construccion and in the industry.

Sorghum the rich food• Carbohydrates 70% High • Protein 8 –15% • Mean = 9% Average • Fat 3.4% Average • Vitamin A 21 RE Average • Ash 1.5% Low • Phosphorus 368mg High • Iron 5.7mg Average • Calcium 21mg Average• Potassium 220mg Average• Amino Acid Profile Poor• Micro Nutrients Excellent

ESSENTIAL AMINO ACIDS CONTAINED IN SORGHUM, CORN AND WHEAT.

AVERAGE COMPOSITION OF MAJOR CONSTITUENTS

Main sorghum producer countries.

Main sorghum importers countries

Main sorghum exporters countries

Sorghum in Mexico.

• The national production in mexico in sorghum crops is: 46.4% in irrigated crops and 53.6% in temporary crops.

• The sorghum’s crops surface in 2007 in Mexico was 1.87 millions of has. Wich is 12.35 of the national surface for the agriculture.

Main sorghum producer states in Mexico.

• Tamaulipas 60%.• Guanajuato 21%.• Sinaloa 10%.• Michoacan 8%.• Nayarit 5%.• The rest of the states 16%.

SORGHUM’S MANAGEMENT.

EMERGENCE. When the plant first breaks through the soil surface (generally occurs 3 to 10 days after planting).

• Depth and date of planting greatly affect emergence rate. During this period, growth depends on the seed for nutrients and food reserves.

• Planting should be timed so that germination and early growth occur during warm temperatures and so flowering will occur before the hottest period of summer. The time required for emergence is impacted by soil temperature, moisture conditions, depth of planting, and vigor of the seed.

• Cool, wet conditions during this time may favor disease organisms that seriously damage stands. Seed should be treated with a fungicide before planting.

• Weed control should be considered. Producers have pre-plant, pre-emergent, and/or post-emergent herbicides available for use. Herbicides are generally used due to the problems encountered with hoeing or cultivation of large fields. This is very apparent in years with above average rainfall, when mechanical practices are limited by wet soil conditions.

• Three-Leaf Stage Leaves are counted when the collar of the leaf can be seen without tearing the plant apart. The collar is the area where the leaf blade and leaf sheath attach.

• It is important that the date of planting be late enough so that sorghum can grow rapidly during the three-leaf stage.

• While the plant's growth rate depends largely on temperature, this stage usually will occur about 10 days after emergence.

• Since the plant is quite small, relatively slow growth and poor weed control can seriously reduce yield.

• As the growing point is still below the soil surface, much of the leaf area can be removed (by hail or insects) without killing the plant. However, sorghum does not recover as vigorously as corn.

• Five-Leaf Stage Approximately 3 weeks after it emerges a sorghum plant has 5 leaves fully expanded; its root system is developing rapidly and roots produced at the lower nodes may push the lower leaf off the plant. This usually does not cause difficulty in identifying the five-leaf stage because the lower leaf has a rounded tip and the second leaf is pointed (Figure 1).

• The growing point is still below the soil surface so leaf loss will not necessarily kill the plant. Regrowth is more vigorous than at the three-leaf stage but still less vigorous than corn.

• During the five-leaf stage the potential for the plant to develop is determined.

• Weed competition, nutrient and water stress, or other problems such as insect damage at the five-leaf stage, can seriously reduce yields if they are not corrected.

• The plant enters its "grand period of growth" in the five-leaf stage. Dry matter accumulates at nearly a constant rate until maturity, if growing conditions are satisfactory.

• Growing Point Differentiation About 30 days after sorghum emerges.

• About one-third of the total leaf area has fully developed; 7 to 10 leaves depending on maturity class. The lower 1 to 3 leaves may have been lost.

• Growth and nutrient uptake are rapid during the growing point differentiation stage. Adequate supplies of nutrients and water are necessary to provide maximum growth.

• Growing point changes from vegetative (leaf producing) to reproductive (head producing). The total number of leaves has been determined and potential head size will soon be determined.

• Sorghum plants are now quite competitive which helps maintain good weed control the remainder of the growing season.

• Time from planting to growing point differentiation generally is about one-third of the time from planting to physiological maturity (maximum dry weight).

• Flag Leaf Stage Following growing point differentiation, rapid culm elongation and rapid leaf development occur simultaneously until the flag leaf (final leaf) is visible in the whorl.

• Most leaves are fully expanded except the final 3 to 4 leaves.

• About 80 percent of the total leaf area is present. Light interception is approaching maximum.

• The lower 2 to 5 leaves have been lost. Any reference to leaf number from now on should be from the top, counting the flag leaf as leaf number 1.

• Growth and nutrient uptake continue at a rapid rate. While only about one-fifth of the total growth has occurred, nutrient uptake is far greater with more than 40 percent of the potassium already being taken up. Adequate supplies of nutrients and water are necessary to provide maximum growth.

• The head is developing. • Sorghum plants are now quite competitive which helps

maintain good weed control the remainder of the growing season

Boot Stage . • All leaves are now fully expanded,

providing maximum leaf area and light interception. The head has now developed to nearly full size and is enclosed in the flag-leaf sheath.

• Rapid growth and nutrient uptake are continuing.

• Severe moisture stress or herbicide injury during the Boot Stage may prevent the head from exerting completely from the flag-leaf sheath. This prevents complete pollination at flowering time.

• Except for the peduncle (see Figure 1) culm elongation is essentially complete.

• Peduncle elongation is beginning and will result in exertion of the head from the flag-leaf sheath.

• Potential head size has been determined.

• Half-Bloom Stage • Half-bloom is usually defined as when one-

half of the plants in a field or area are in some stage of bloom. However, because an individual sorghum head flowers from the tip downward over 4 to 9 days, half-bloom on an individual plant is when the flowering has progressed half-way down the head.

• Time required from planting to half-bloom depends on the maturity of the hybrid and environmental conditions; however, it usually represents two-thirds of the time from planting to physiological maturity.

• Following the boot stage the peduncle grows rapidly extending the head through the flag-leaf sheath. Even in combine sorghums, the peduncle is not reduced in length as is the rest of the stalk. Although height of combine-sorghum plants has been reduced, heads are well above the leaves, which makes combining easier.

• At half-bloom approximately one-half of the total dry weight of the plant has been produced. However, nutrient uptake has reached nearly 70, 60, and 80 percent of total for N, P2O5, and K2O, respectively.

• At this time grain formation begins; therefore, any limitation in plant size, leaf area, or plant numbers can no longer be corrected

• If environmental conditions are favorable, the sorghum yield can still be increased by increasing the seed weight.

• Sever moisture stress can result in "blasting" and poor head filling.

• As mentioned earlier hybrid maturity and planting date should be chosen so flowering will not occur when severe hot, dry weather is normal.

• Soft-Dough Stage Between half-bloom and soft-dough the grain fills rapidly; almost half of its dry weight is accumulated in this period.

• The stalk weight increases slightly following half-bloom; then, because grain is forming rapidly, the stalk loses weight. The loss in stalk weight may account for as much as 10 percent of the grain weight.

• Final yield depends on the rate that dry matter accumulates in the grain and the length of time that it accumulates.

• As long as the hybrid is able to mature before frost, the dry matter accumulation will be high if environmental conditions are favorable.

• The selection of later maturing grain sorghum hybrids has an advantage over early maturing varieties if: 1) the hybrid can mature before frost and 2) flowering does not coincide with severe moisture stress.

• Dry matter accumulation rates do not vary much among hybrids.

• Nitrogen and Phosphorus uptake is still rapid and Potassium uptake is close to 90 percent and starting to decline.

• Lower leaves are still being lost with 8 to 12 functional leaves remaining.

• Hard-Dough Stage By hard-dough stage, about three-fourths of the grain dry weight has accumulated. Nutrient uptake is essentially complete.

• Severe moisture stress or a freeze before the grain matures will result in light, chaffy grain.

• The stalk has declined to its lowest weight. Additional leaves may have been lost.

• Physiological Maturity • Maximum total dry weight of the plant has

occurred. The time from flowering to physiological maturity varies with hybrid and environmental conditions; however, it represents about one-third of the total time from planting.

• Grain moisture content at physiological maturity is usually between 25 and 35 percent, but varies with hybrid and growing conditions.

• If temperature and moisture conditions are favorable, branches may start to grow from several of the upper nodes (places where leaves attach).

• Physiological maturity can be determined by the dark spot on the opposite side of the kernel from the embryo. The kernel on the left is physiologically mature; the one on the right is not.

• To reap maximum yields of silage or high-moisture grain, harvest as near to physiological maturity as possible.

• The plant will not reach physiological maturity and proper moisture content for normal harvest at the same time.

• The time required between physiological maturity and a grain moisture suitable for harvest depends on the hybrid and weather conditions.

• Stalk weight may increase slightly near physiological maturity.

• After physiological maturity, the remaining functional leaves may stay green or die and brown rapidly.

• Nutrient uptake is basically complete.

The plants swoing can go from 85,000 to 150,000 plants by ha. Depending on the seed that the producer’s choose.

Diseases caused by bacteria.

• Bacterial leaf stripe.- pathogen Pseudomonas rubrisubalbicans

• symptoms: irregularly shaped, dark red lesions on leaves and leaf sheaths.

• Control suggested.- crop rotation, destruction of crop residue and planting resistant cultivars or hybrids.

Bacterial leaf spot.

• Pathogen Pseudomonas syringae.• Initial symptoms consist en water soacked

spots on the lower leaves, within a short period these irregular, elliptic lesions assume a reddish hue.

• Control : crop rotation, destruction of infested debris and selection of seed from disease- free plants.

Bacterial soft rot.

• Pathogen Erwinia crysanthemi pv. Chrysantemi.

• Symptoms .-necrotic or heavily pigmented stripes or blotches on upper leaves; stalk and leaf tissue rotted in whorls.

Diseases caused by fungi.

• Seedling diseases .-damage weathered or moldy seed .

• Pathogens. Pythium spp. Fusarium spp. Aspergillus spp. Rizoctonia spp. Phoma spp.

• Control.- captan, thiram, metalaxyl and fosetyl Al. wich are systemic products.

Leaf anthracnose .• Pathogen.-Glomerella graminicola. • Control.- the use of resistant cultivars.

Gray leaf spot.• Pathogen C. sorghi Ell &Ev.• Control.- Use of tolerant or resistant cultivars,

crop rotation and sanitation to reduce surface residue and kill surviving crop plants.

Panicle and grain anthracnose. • Pathogen.- Colletotrichum graminicola. • Control.- the destruction of primary inoculum,

use po pathogen free-seed or seed treated with fungicides.

Storage molds .

• Symptoms of damage for a fungal colonization include discoloration in grain(darkening) of the embryo or germ and molding, heating and mustiness of the grain.

• Causal organisms and mycotoxins: Aspergillus spp. Penicillium spp. A.restrictus. A glaucus. Control.- the most comun method is prevention by drying or cooling the grain at wich fungi cannot grow (moisture less than 13% and temperature below 5 Celcius degrees).

Diseases caused by viruses and virus like organisms.

• Barley yellow dwarf virus.- attack S. bicolor.- no symptoms shown. Transmited by an aphid.

• Panicum mosaic virus.- S.bicolor.- symptoms: fain. Smaal clorotic lesion.- by a mechanical transmition.

• Rice stripe virus.-S. halapense.- symptoms.- chlorosis,chlorotic strip.- transmite by leafhopper.

• Maize rough dwarf virus.- S.bicolor.- chlorosis – transmited by planthopper.• Maize mosaic virus.- S.bicolor.

chlorotic striping. Transmited by planthopper.• Control.- cultural practices that

minimize the virus source.

Nematodes.

Symptoms:• Root knots or galls.• Root lesions.• Abnormal or reduced root development.

Control.

• Quarantine and sanitization.• Cultural practices (crop rotation).• Physical treatments (steam sterilization or hot

water dips).• Biological control (fungi, bacteria, insects and

predacious nematodes).• Use of resistant cultivars.• Chemical control(insecticide-nematicides like

carbamates and organophosphates).

Beneficial microorganisms.

• Vesicular-arbuscular mycorrhizae (VAM). Endogenaceae.

• Glomus.• Gigaspora.• Acaulospora.• Sclerocystis.

Insect pests.

Soil insects.

• White grub Phylophaga crinite (Burmeister).• Cut worm larvae.• Some species of climbing or army cutworms.• Diabrotica undecimpunctata howardi Barber.

Foliage feeders.

•Greenbug Schizaphis graminum (Rondani).•The corn leaf aphid Rhopalopsiphum maidis (Fitch).•The sugar cane aphid Melanaphis sachari (Zehntner).•The yellow sugar cane aphid Sipha flava Forbes.•Shoot bug Peregrinus maidis (Ashmead).•The spittlebug Poophiluscostalis Walker.•The chinch bug Blissusleucopterus (Say).•Spider mites Oligonycus spp.

Stem feeders.

• Pink borer Sesamia inferens Walker.• Sugar cane borer Diatraea spp.• Maize stalk borer Busseola fusca Fuller.

Head feeders.

• Larvae of sorghum midge Contarinia sorghicola (Coquillett).

• Larvae of cornearworm Heliothis zea (Boddie).• Young larvae of sorghum webworm Nola

sorghiella

THANKS FOR YOUR TIME AND ATENTION..