Unit 3 /10-31-22

Cytoplasmic male sterility

not be great, hybrid benefits only come from first gen seeds from non hybrid parents

High yields vigor and uniformity Expensive Cannot save seeds

Self pollinate or cross-pollinate with other plants

Keep in cool, dry place Paper packets are best kept in tightly closed jars or containers and maintained around 40°F with low humidity.

Water, temp, oxygen light is not required for all seeds

• Water is the critical first step • Without water, seeds will remain dormant • Too much water causes seeds to rot • Too little water causes the embryos to die • Try not to displace seeds by excessive flooding. Germination

• All viable seeds need oxygen. • Seed respiration rate increases dramatically during germination. • Growing medium must be loose and well-aerated. • Too much water can inhibit germination!

• Some seeds require light to germinate. - Dill, • Some seeds require darkness to germinate. - Kale and cauliflower • Some light is not a factor in germination.

• When sowing light-requiring seeds, do not bury them. • Cover them lightly with fine peat moss or fine vermiculite. • Provide supplemental light for 6-12” above the seeds for 18 h per day.

• Each plant has a specific optimum and range within which germination will occur. • Cool-season Crop - Peas = Hypogeal • Warm-season crops barley, oats, canola = 40-68

• Asparagus, beets, broccoli, Brussels sprouts, chives, cabbage, carrots, cauliflower, Swiss chard, kale, leek, lettuce, onion, parsnips, peas, radishes, spinach, and turnips. Less susceptible to frost damage

• Beans, corn, cucumbers, eggplant, melons, peppers, zucchini and summer squash, pumpkin and winter squash, sweet potato, tomato, watermelon.

• After germination, seedlings must receive bright light. • Insufficient light causes seedlings to “stretch”

• Ideally, seedlings should be dark green and sturdy. • Symptoms of nutrient deficiencies include pale yellow foliage, purpling of leaves (older plants). Very sensitive to water

• If plants have not been seeded in individual containers, they must be transplanted. • What happens if you leave the seedlings too long? • Ideal time is when the first true leaves appear between the cotyledons (called “seed” leaves).

light, pot too long, water, fertilizer

• Carefully dig up the small plants with a knife or wooden pot ladle. • Gently ease them apart in small groups to make separating individuals easier (do not tear roots). • Handle small seedling by their leaves, not their delicate stem • After transplants, seedlings need nutrients. • Some commercial soil mixes have fertilizer already added. • If you are using media without fertilizers, you will need to add supplemental nutrients. • Young seedlings are easily damaged by too much fertilizer, especially if they are under moisture stress.

• Garden containers come in many different types and materials. • Examples wooden or plastic flats, trays, cell-packs, and pots for starting seeds. • Drainage at the bottom of the container is critical for plants. • Drainage allows water in the soil to drain freely so adequate air is available for the roots. • Few plants can survive in stagnant water!

rice

approx. 80%

Nitrogen