Self-pollination

**Occurrence of Self-Pollination**:
– Self-pollination is common in legumes like peanuts and soybeans, orchids, peas, sunflowers, and tridax.
– Self-pollinating plants have small flowers shedding pollen directly onto stigma.
– It allows growth in areas with scarce pollinators.

**Types of Self-Pollination Flowers**:
– 80% of flowering plants are hermaphroditic, while 5% are monoecious.
– Self-pollinating plants include orchids, sunflowers, and dandelions.
– Hermaphrodite and monoecious species can self-pollinate, while dioecious plants are unisexual.

**Advantages and Disadvantages of Self-Pollination**:
– Advantages include maintaining stable traits, no dependency on pollinators, and less wastage of pollen.
– Disadvantages are lack of variation, inbreeding depression, and genetic defects.

**Mixed Mating Systems**:
– About 42% of flowering plants exhibit a mixed mating system.
– Individual plants may produce self-pollinated, out-crossed, or mixed progeny types.
– Different types of flowers can lead to diverse progeny types.

**Evolutionary Aspects and Mechanisms of Self-Pollination**:
– Mixed mating systems are an evolutionary enigma in plants.
– Self-fertilization in plants has evolutionary consequences.
– Mechanisms include anther stepping onto stigma in certain orchids and stigmatic rostellum receptivity promoting auto-pollination.